JP2007154658A - Compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly efficient refrigerating cycle by reducing the amount of the refrigerating machine oil discharged from a compressor while being mixed in a working fluid to increase the reliability and performance of the compressor. <P>SOLUTION: A cover member 32 is provided on the upper surface 7e of a main bearing member 7. A space 31 between the main bearing member 7 and the cover member 32 is a passage through which the refrigerating machine oil lubricating a main bearing 7a is returned to an oil sump 16. The refrigerating machine oil which returns to the oil sump 16 is isolated from a main flowing place of the working fluid. With this, refrigerating machine oil and the working fluid are prevented from being mixed with each other, and the amount of the refrigerating machine oil discharged from the compressor together with the working fluid is reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hermetic rotary compressor used for a refrigerator-freezer, an air conditioner, or the like.

Hermetic rotary compressors are often used in refrigerators and air conditioners because of their compactness and simple structure. Non-patent document 1 describes the configuration of a hermetic rotary compressor such as a rotary compressor. The configuration of the hermetic rotary compressor will be described below with reference to FIGS. 4 to 5 by taking a rotary compressor as an example.
FIG. 4 is a longitudinal sectional view of a conventional rotary compressor. The rotary compressor shown in the figure includes a sealed container 1, a shaft 2 having an eccentric portion 2a, a cylinder 3, a roller 4, a vane 5, a spring 6, a main bearing 7a that supports the shaft 2, a discharge hole 7c, and the like. Main bearing member 7, sub-bearing member 8 having sub-bearing 8 a that supports shaft 2, stator 11 that is shrink-fitted inside sealed container 1, and rotor 12 that is shrink-fitted to shaft 2. Composed. Also, spiral grooves 7b and 8b are provided on the sliding surfaces of the main bearing 7a and the auxiliary bearing 8a. Of the above-described configuration, a portion constituted by the stator 11 and the rotor 12 is formed as a rotary electric motor part, and a suction chamber and a compression chamber (not shown) are formed in the cylinder 3, and actuates in accordance with the rotational movement of the rotor 12 A portion that compresses the fluid is referred to as a compression mechanism portion.
Further, a plurality of notches 11 a for providing a working fluid flow path are provided on the outer peripheral side of the stator 11, and a gap 18 is provided between the stator 11 and the rotor 12. The sealed container 1 includes an introduction terminal 13 for energizing the stator 11, a suction pipe (not shown) for guiding the working fluid from the refrigeration cycle into the cylinder 3, and working fluid from the inside of the closed container 1. This is a configuration in which a discharge pipe 15 that discharges to the refrigeration cycle and an oil reservoir 16 in which refrigeration oil is stored are provided.

The operation of the rotary compressor having the above configuration will be described.
When the stator 11 is energized through the introduction terminal 13 to rotate the rotor 12, the roller 4 performs eccentric rotational movement by the eccentric portion 2a, and the volumes of the suction chamber and the compression chamber change. Accordingly, the working fluid is sucked into the suction chamber and compressed in the compression chamber. The compressed working fluid is ejected into the lower space 17 of the rotary electric motor section through the discharge hole 7c. The main flow field of the ejected working fluid becomes a strong swirl flow due to the rotational movement of the rotor 12 due to the collision of the working fluid against the lower end surface 12 a of the rotor 12. Thereafter, the working fluid passes through the notch 11 a and the gap 18, and is ejected to the upper space 19 of the rotary electric motor unit, and then discharged from the discharge pipe 15 to the outside of the sealed container 1.
On the other hand, the refrigerating machine oil in the oil sump 16 is pumped up to the eccentric portion 2a while lubricating the auxiliary bearing 8a through the spiral groove 8b as the shaft 2 rotates. Part of the refrigerating machine oil pumped up is the suction chamber or the fitting portion of the eccentric portion 2a and the roller 4 and the clearance between the upper and lower end surfaces of the roller 4 and the main bearing member 7 and the auxiliary bearing member 8 while lubricating and sealing. It flows into the compression chamber, is mixed with the working fluid, and is discharged from the discharge hole 7 c to the lower space 17.
Further, the remaining refrigerating machine oil passes through the spiral groove 7b as the shaft 2 rotates, and is pumped up to the upper end 7d of the main bearing 7a while lubricating the main bearing 7a. Thereafter, it overflows from the upper end portion 7d and flows on the upper surface 7e of the main bearing member 7, and a part of the refrigerating machine oil is wound up by the swirling flow of the working fluid generated in the lower space 17 and mixed with the working fluid, and the rest The refrigerating machine oil returns to the oil reservoir 16 through a plurality of communication holes 7 f provided on the outer peripheral side of the main bearing member 7. A part of the refrigerating machine oil mixed with the working fluid is separated by gravity, centrifugal force of the swirling flow or the like in the lower space 17 and the upper space 19 of the rotary electric motor unit and returned to the oil sump 16, and the remaining refrigerating machine oil is , And discharged from the discharge pipe 15 to the outside of the sealed container 1 together with the working fluid.

As described above, in a hermetic compressor such as a rotary compressor, a part of the refrigerating machine oil stored in the oil reservoir 16 is discharged from the hermetic container 1 during the operation of the compressor. As a result, in a compressor with a large amount of refrigerating machine oil discharged, the oil level of the refrigerating machine oil in the oil sump 16 is lowered, so that the amount of refrigerating machine oil supplied to the compression mechanism is insufficient, and lubrication becomes insufficient and abnormal wear occurs. As a result, the reliability is reduced, and the working fluid is not sufficiently sealed in the compression mechanism, resulting in a reduction in efficiency.
Moreover, since the refrigeration oil discharged from the compressor adheres to the inner wall of the heat exchanger and reduces the heat transfer coefficient between the working fluid and the inner wall, the performance of the refrigeration cycle is lowered. Therefore, the amount of refrigerating machine oil mixed and discharged with the working fluid is reduced.
As a configuration for reducing the discharge amount of refrigerating machine oil, for example, as disclosed in Patent Document 1, there is a method of using an oil separation plate provided on an upper portion of a rotor 12 of a rotary compressor. FIG. 5 shows a detailed sectional view of the periphery of the oil separation plate. The rotor 12 is provided with an upper end plate 12c and a lower end plate 12d that close the insertion hole of the permanent magnet 12b, and a plurality of through holes 12e formed through the rotor 12 in the vertical direction, and through holes An oil separation plate 21 disposed above the outlet 12e and forming an oil separation space 20 between the rotor 12 and the upper end plate 12c of the rotor 12 is fixed to the rotor 12 by a fixing member 22.

In the compressor configured as described above, a part of the working fluid including the oil droplets of the refrigerating machine oil discharged from the compression mechanism portion to the lower space 17 of the rotary electric motor passes through the through hole 12e provided in the rotor 12. Into the oil separation space 20. And here, working fluid is discharged radially from the outer periphery outlet of the oil separation plate 21 by centrifugal force, and sprayed to the coil end 11b of the stator 11 to separate the working fluid and the refrigerating machine oil contained therein. Then, only the working fluid from which the refrigerating machine oil is separated rises and is discharged to the outside from the discharge pipe 15 provided at the upper part in the sealed container 1. On the other hand, the refrigerating machine oil adhering to the coil end 11 b of the stator 11 is transmitted downward and returned to the oil sump 16 stored at the bottom of the sealed container 1.
"Refrigeration and Air Conditioning Handbook, New Edition 5th Edition, Volume II Equipment", Japan Refrigeration Association, 1993, Paragraphs 30-43 JP-A-8-28476 (Section 6, FIGS. 1 to 3)

As described above, in the conventional rotary compressor, when the refrigerating machine oil lubricates and seals the fitting portion between the eccentric portion 2a and the roller 4 and the gap between the roller 4 and the main bearing member 7 and the auxiliary bearing member 8, the cylinder 3 Or mixed with the working fluid or mixed with the working fluid by being swirled into the swirling flow in the lower space 17 while overflowing from the upper end 7d of the main bearing 7a and returning to the oil sump 16 together with the working fluid. It was discharged from the discharge pipe 15 to the outside of the sealed container 1.
Further, the structure shown in FIG. 5 is used as means for separating from the working fluid. In such a separation method, even if the refrigerating machine oil mixed with the working fluid is sprayed onto the coil end 11b, it does not adhere completely, and the operation is particularly effective. When the amount of refrigerating machine oil mixed with the fluid is large, the discharge amount of refrigerating machine oil cannot be reduced sufficiently. Further, the working fluid that flows from the lower space 17 to the upper space 19 only functions for the working fluid that passes through the through hole 12 e provided in the rotor 12, and that passes through the notch 11 a and the gap 18. It is impossible to separate refrigeration oil from

  Therefore, the present invention is for solving the above-mentioned problems, and reduces the amount of refrigeration oil discharged from the compressor mixed with the working fluid, improves the reliability and performance of the compressor, and is highly efficient. The purpose is to obtain a refrigeration cycle.

According to a first aspect of the present invention, there is provided a compressor according to the first aspect of the present invention, wherein a rotary electric motor unit including a stator and a rotor, and a lower space is provided below the rotary electric motor unit and are rotated by the rotor. A compression mechanism portion that compresses the working fluid, and a hermetic container including the rotary electric motor portion and the compression mechanism portion and having a sump of lubricating oil in a bottom portion, and the compression mechanism portion includes at least the rotor A shaft to which the shaft is fixed, a main bearing that supports the shaft, oil supply means that supplies the lubricating oil from the oil reservoir to the main bearing, and the lubricating oil that has lubricated the main bearing is returned to the oil reservoir. A compressor having an oil return path, wherein the oil return path is isolated from a main flow field of the working fluid discharged from the compression mechanism portion into the lower space.
According to a second aspect of the present invention, in the compressor according to the first aspect, the oil return path is a path for returning the lubricating oil discharged from the upper end portion of the main bearing to the oil sump. And
According to a third aspect of the present invention, in the compressor according to the first or second aspect, the compression mechanism portion includes a cylinder and a main bearing member that forms the main bearing on the upper side of the cylinder, A cover member that covers at least a part of the main bearing member is provided on the upper surface side of the main bearing member, and the oil return path is a space between the main bearing member and the cover member.
According to a fourth aspect of the present invention, in the compressor according to the third aspect, the shape of the cover member is a shape along the upper surface of the main bearing member.
According to a fifth aspect of the present invention, in the compressor according to the third aspect, the shape of the cover member is a circle centered on the shaft.
According to a sixth aspect of the present invention, in the compressor according to any one of the first to fifth aspects, carbon dioxide is used as the working fluid.

  According to the compressor of the present invention, the lubricating oil that isolates the oil return path from the main flow field of the working fluid and returns to the oil sump, for example, the refrigerating machine oil overflowing from the upper end 7d of the main bearing 7a is mixed with the working fluid. By reducing the amount of refrigerating machine oil mixed and discharged from the compressor to the working fluid, the reliability and efficiency of the compressor can be improved, and a highly efficient refrigerating cycle can be obtained. .

In the compressor according to the first embodiment of the present invention, the oil return path is isolated from the main flow field of the working fluid discharged from the compression mechanism portion into the lower space. According to the present embodiment, since the lubricating oil that flows through the oil return path and returns to the oil sump is isolated from the main flow field of the working fluid, it is caught in the swirling flow generated in the lower space and mixed with the working fluid. It is prevented. Therefore, the amount of refrigerating machine oil discharged outside the sealed container can be reduced.
According to the second embodiment of the present invention, in the compressor according to the first embodiment, the oil return path is a path for returning the lubricating oil discharged from the upper end portion of the main bearing to the oil sump. According to the present embodiment, the lubricating oil discharged from the upper end portion of the main bearing can be returned to the oil reservoir without being mixed with the working fluid.
According to a third embodiment of the present invention, in the compressor according to the first or second embodiment, the compression mechanism unit includes a cylinder and a main bearing member that forms a main bearing on the upper side of the cylinder, and the main bearing A cover member that covers at least a part of the main bearing member is provided on the upper surface side of the member, and the oil return path is a space between the main bearing member and the cover member. According to the present embodiment, since the oil return path is isolated from the main flow field of the working fluid by the cover member, the lubricating oil can be returned to the oil sump without being mixed with the working fluid.
In the compressor according to the third embodiment, the fourth embodiment of the present invention is such that the shape of the cover member is a shape along the upper surface of the main bearing member. According to the present embodiment, it is possible to minimize the decrease in the space volume of the lower space, and it is possible to minimize the decrease in the oil separation effect in the lower space.
In the compressor according to the third embodiment, the fifth embodiment of the present invention is such that the shape of the cover member is a circle centered on the shaft. According to this embodiment, the processing of the cover member is simplified and can be manufactured at low cost.
The sixth embodiment of the present invention uses carbon dioxide as a working fluid in the compressors according to the first to fifth embodiments. Carbon dioxide has a small density difference from the refrigerating machine oil, and the refrigerating machine oil is easily caught in the flow of carbon dioxide, but according to the present embodiment, the oil return path is isolated from the main flow field of carbon dioxide, Since the refrigerating machine oil returning to the oil sump is prevented from being caught in the flow of carbon dioxide, environmentally friendly carbon dioxide can be used as a working fluid.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The rotary compressor according to the first embodiment of the present invention has substantially the same configuration as the conventional rotary compressor described with reference to FIG. 4, and the same reference numerals are applied to the same functional parts.
FIG. 1 is a longitudinal sectional view of a rotary compressor according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of the compression mechanism portion of the rotary compressor shown in FIG. 1, and corresponds to a cross section taken along arrows Z1-Z1 in FIG. FIG. 3 is a cross-sectional view in the lower space of the rotary motor portion of the rotary compressor shown in FIG. 1, and corresponds to a cross section taken along arrows Z2-Z2 in FIG.
The rotary compressor shown in the figure is composed of a hermetic container 1, a compression mechanism part arranged below the inside of the hermetic container 1, and a rotary electric motor part arranged on the upper part thereof. The compression mechanism portion has an eccentric portion 2 a and is rotatable about the central axis L, the cylinder 3, and fitted to the eccentric portion 2 a so as to be eccentric inside the cylinder 3 as the shaft 2 rotates. A roller 4 that rotates, a vane 5 that reciprocates inside the vane groove 3a of the cylinder 3 while contacting the tip of the roller 4, a spring 6 that presses the vane 5 against the roller 4, a main bearing 7a that supports the shaft 2, A main bearing member 7 that has a discharge hole 7c for discharging the working fluid from the cylinder 3 and closes the opening on the upper side of the cylinder 3 and a sub bearing 8a that supports the shaft 2 and has an opening on the lower side of the cylinder 3 And a secondary bearing member 8 that closes the portion. The sliding surfaces of the main bearing 7a and the auxiliary bearing 8a are provided with spiral grooves 7b and 8b as oil supply means for supplying lubricating oil, respectively. A space between the cylinder 3 and the roller 4 sandwiched between the main bearing member 7 and the sub bearing member 8 is divided into a suction chamber 9 and a compression chamber 10 by a vane 5.
On the other hand, the rotary motor unit includes a stator 11 fixed inside the sealed container 1 and a rotor 12 fitted to the shaft 2. On the outer peripheral side of the stator 11, a plurality of notches 11 a for providing a working fluid flow path are provided, and a gap 18 is provided between the stator 11 and the rotor 12. Then, an introduction terminal 13 for energizing the stator 11 from the outside of the sealed container 1 and a discharge pipe 15 for discharging the working fluid from the inside of the sealed container 1 to the refrigeration cycle are provided on the upper part of the sealed container 1, A suction pipe 14 that guides the working fluid from the refrigeration cycle to the suction chamber 9 is provided at the side of the sealed container 1, and an oil reservoir 16 that stores refrigerating machine oil is provided at the bottom of the sealed container 1. .

In the rotary compressor of the present embodiment, in addition to the above configuration, a cover member 32 is installed on the upper surface 7e side of the main bearing member 7 (that is, on the lower space 17 side of the rotary motor portion) with the upper surface 7e and the space 31 therebetween. It is configured. The size of the space 31 overflows from the upper end 7d of the main bearing 7a and is approximately the same as the thickness of the flow of the refrigerating machine oil flowing through the upper surface 7e of the main bearing member 7. The thickness of the flow of the refrigerating machine oil increases as the amount of refrigerating machine oil supplied to the main bearing 7a increases and the viscosity of the refrigerating machine oil increases.
The cover member 32 has a circular shape centering on the shaft 2 and a convex portion 32a that protrudes into the center of the main bearing member 7 and covers the main bearing 7a in order to have a shape along the upper surface 7e of the main bearing member 7. Is provided. The convex portion 32a is provided with a hole 32b through which the shaft 2 passes and a flange portion 32c around the shaft 32, and a gap 33 between the shaft 2 and the hole 32b is configured to be as small as possible without causing sliding. ing.
The circular edge 32d on the outer peripheral side of the cover member 32 is sized to cover the communication hole 7f of the main bearing member 7 to about half, and a flange 32e is provided on the edge 32d. Further, a discharge hole 32 f is provided at a portion of the cover member 32 facing the discharge hole 7 c of the main bearing member 7 so that the working fluid discharged from the discharge hole 7 c flows out to the upper side of the cover member 32. . A thick part 32g is provided around the discharge hole 32f of the cover member 32 so that the discharge hole 32f communicates with the discharge hole 7c without any gap, and the thick part 32g is brought into direct contact with the upper surface 7e of the main bearing member 7. ing.

Next, the operation of the rotary compressor of this embodiment will be described.
When the stator 11 is energized through the introduction terminal 13 to rotate the rotor 12, the roller 4 is eccentrically rotated by the eccentric portion 2 a of the shaft 2, and the volumes of the suction chamber 9 and the compression chamber 10 are changed. Accordingly, the working fluid is sucked into the suction chamber 9 from the suction pipe 14 and compressed in the compression chamber 10. The compressed working fluid is jetted into the lower space 17 of the rotary motor section through the discharge hole 7c of the main bearing member 7 and the discharge hole 32f of the cover member 32. In the main flow field of the ejected working fluid, the working fluid collides with the lower end surface 12 a of the rotor 12 and becomes a strong swirl flow by the rotational movement of the rotor 12. After that, the working fluid passes through the gap 18 between the stator 11 and the rotor 12 and the notch 11a of the stator 11 and is ejected to the upper space 19 of the rotary motor unit, and then is discharged from the discharge pipe 15 to the outside of the sealed container 1. Discharged.
On the other hand, the refrigerating machine oil in the oil sump 16 is pumped up to the eccentric portion 2a of the shaft 2 while lubricating the auxiliary bearing 8a through the spiral groove 8b of the auxiliary bearing 8a as the shaft 2 rotates. Part of the refrigerating machine oil pumped up is a suction chamber 9 while lubricating and sealing the gap between the eccentric portion 2 a and the fitting portion of the roller 4 and the upper and lower end surfaces of the roller 4 and the main bearing member 7 and the auxiliary bearing member 8. Or flows into the compression chamber 10, is mixed with the working fluid, passes through the discharge hole 7 c of the main bearing member 7 and the discharge hole 32 f of the cover member 32, and is discharged into the lower space 17.
A part of the discharged refrigerating machine oil is separated by gravity, centrifugal force or the like in the lower space 17 or the upper space 19 of the rotary electric motor unit, but the remainder is not separated but is discharged together with the working fluid in the discharge pipe 15. To the outside of the sealed container 1.
The remaining refrigeration oil passes through the spiral groove 7b of the main bearing 7a as the shaft 2 rotates, and is pumped up to the upper end 7d of the main bearing 7a while lubricating the main bearing 7a. Thereafter, it overflows from the upper end portion 7d, flows in the space 31 between the cover member 32 and the upper surface 7e of the main bearing member 7, and when reaching the edge 32d of the cover member 32, the flow is changed downward by the flange portion 32e. It returns to the oil sump 16 through a plurality of communication holes 7f provided on the outer peripheral side of the member 7.

As described above, in the rotary compressor of this embodiment, the oil return path from the refrigerating machine oil that has lubricated the main bearing 7a and overflowed from the upper end 7d to the oil sump 16 is the cover member 32 and the main bearing member 7. A space 31 between the upper surface 7e and the main flow field of the working fluid discharged from the discharge hole 32f to the lower space 17 of the rotary electric motor unit. Therefore, it is possible to completely prevent the refrigerating machine oil that overflows from the upper end portion 7d of the main bearing 7a and returns to the oil sump 16 from being mixed with the working fluid.
Therefore, the rotary compressor of the present embodiment can reduce the amount of refrigerating machine oil discharged to the outside of the hermetic container 1 together with the working fluid. That is, the oil level of the refrigerating machine oil in the oil sump 16 is reduced, and the compression mechanism portion is not sufficiently lubricated to reduce reliability, and the compression mechanism portion is not sufficiently sealed to reduce efficiency. be able to.
In addition, the refrigeration oil discharged from the compressor adheres to the inner wall of the heat exchanger tube of the heat exchanger, reducing the effect of lowering the heat transfer coefficient between the working fluid and the inner wall surface of the heat exchanger tube. Can be improved.

Further, in the rotary compressor of the present embodiment, the flange portion 32 c is provided on the convex portion 32 a of the cover member 32, and the gap 33 between the shaft 2 and the cover member 32 is reduced. With this configuration, the refrigerating machine oil overflowing from the upper end portion 7d of the main bearing 7a is prevented from leaking from the gap 33 to the upper side of the cover member 32, that is, the lower space 17 side of the rotary motor portion, and being caught in the flow of the working fluid. be able to. Accordingly, the amount of the refrigerating machine oil discharged together with the working fluid to the outside of the sealed container 1 can be further reduced, so that the effect of the cover member 32 can be further improved.
Further, since the shape of the cover member 32 (cross-sectional shape shown in FIG. 1) is a shape along the upper surface 7e of the main bearing member 7, the refrigerator oil is provided between the cover member 32 and the upper surface 7e of the main bearing member 7. Even if a sufficient space 31 is provided to return the space, a decrease in the space volume of the lower space 17 can be minimized. Therefore, due to the large space volume of the lower space 17 of the rotary motor unit, the effect of separating the refrigeration oil from the working fluid by reducing the flow velocity of the working fluid and the retention time of the working fluid being increased, The reduction in the effect of separating the refrigerating machine oil can be minimized.
Further, since the shape of the cover member 32 (planar shape shown in FIG. 3) is a circle centered on the shaft 2, the processing of the cover member 32 is simple and inexpensive, and the upper end portion 7d of the main bearing 7a. Refrigerating machine oil overflowing from any position in the circumferential direction can be efficiently returned to the oil sump 16. Needless to say, the cover 32 member does not necessarily have a circular shape, and can function to reduce oil discharge as long as the space 31 communicates from the main bearing 7 a to the oil reservoir 16.

Further, since the flange 32e is provided on the edge 32d on the outer peripheral side of the cover member 32, the space 31 is opened only to the communication hole 7f of the main bearing member 7 communicating with the oil reservoir 16, so that the rotary motor It becomes difficult for the flow of the working fluid in the lower space 17 of the part to flow into the space 31, and mixing of the working fluid and the refrigerating machine oil can be prevented. As a result, the amount of the refrigerating machine oil discharged together with the working fluid to the outside of the sealed container 1 can be reduced, so that the effect of the cover member 32 can be further improved.
Further, the cover member 32 covers a part of the communication hole 7f of the main bearing member 7, so that the refrigeration oil flowing through the space 31 can easily return to the oil sump 16 through the communication hole 7f, and the lower part of the rotary motor portion. The refrigerating machine oil separated from the working fluid by gravity or centrifugal force in the space 17 can be returned to the oil sump 16 from the portion of the communication hole 7f of the main bearing member 7 that is not covered by the cover member 32. It is possible to prevent the separation of the refrigerating machine oil in the lower space 17.
Further, when carbon dioxide is used as the working fluid, the density difference between the refrigerating machine oil and carbon dioxide is reduced because the density of carbon dioxide is very large compared to the case of using chlorofluorocarbon. Therefore, the refrigerating machine oil overflowing from the upper end portion 7d of the main bearing 7a is likely to be caught in the flow of carbon dioxide, but in this embodiment, the oil return path is isolated from the main flow field of the working fluid, and thus returns to the oil sump. Refrigerating machine oil can be prevented from being caught in the flow of carbon dioxide. For example, when the cover member 32 is installed, the effect becomes more prominent, and environmentally friendly carbon dioxide can be used as the working fluid.

  The compressor according to the present invention has a function of compressing and conveying a working fluid, and is useful for a refrigerant heat pump such as a refrigerator-freezer or an air conditioner. It can also be applied to uses such as vacuum pumps.

The longitudinal cross-sectional view of the rotary compressor in 1st Example of this invention 1 is a cross-sectional view of a compression mechanism portion of the rotary compressor shown in FIG. Cross section in the lower space of the rotary motor section of the rotary compressor shown in FIG. Longitudinal sectional view of a conventional rotary compressor Detailed cross-sectional view around the oil separator plate of a conventional compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Shaft 3 Cylinder 7 Main bearing member 7a Main bearing 7b Spiral groove 7c Discharge hole 7d Upper end part 7e Upper surface 7f Communication hole 11 Stator 12 Rotor 16 Oil sump 17 Lower space 31 Space 32 Cover member

Claims (6)

  A rotary electric motor unit composed of a stator and a rotor, a compression mechanism unit which is arranged with a lower space below the rotary electric motor unit and is rotated by the rotor to compress the working fluid; A sealed container including a rotary motor portion and the compression mechanism portion and having a sump of lubricating oil in a bottom portion, and the compression mechanism portion supports at least the shaft to which the rotor is fixed and the shaft. A compressor having a main bearing, oil supply means for supplying the lubricating oil from the oil reservoir to the main bearing, and an oil return path for returning the lubricating oil that has lubricated the main bearing to the oil reservoir. The compressor is characterized in that the oil return path is isolated from the main flow field of the working fluid discharged from the compression mechanism portion into the lower space.   The compressor according to claim 1, wherein the oil return path is a path for returning the lubricating oil discharged from the upper end portion of the main bearing to the oil reservoir.   The compression mechanism portion includes a cylinder and a main bearing member that forms the main bearing on the upper side of the cylinder, and a cover member that covers at least a part of the main bearing member is provided on the upper surface side of the main bearing member, The compressor according to claim 1, wherein the oil return path is a space between the main bearing member and the cover member.   The compressor according to claim 3, wherein a shape of the cover member is a shape along an upper surface of the main bearing member.   The compressor according to claim 3, wherein the shape of the cover member is a circle centered on the shaft. The compressor according to any one of claims 1 to 5, wherein carbon dioxide is used as the working fluid.

Images