WO2011093086A1

WO2011093086A1 - Fluid machinery

Info

Publication number: WO2011093086A1
Application number: PCT/JP2011/000459
Authority: WO
Inventors: 憲幸小林
Original assignee: サンデン株式会社
Priority date: 2010-01-29
Filing date: 2011-01-27
Publication date: 2011-08-04
Also published as: BR112012018673A2; MX2012008748A; JP2011157831A; CA2787527A1; EP2514972A1; KR20120103744A; CN102725527A; US20120308410A1; EP2514972A4

Abstract

Provided is fluid machinery with improved lubrication performance and reliability. Fluid machinery (1) has a drive unit (4) and a driven unit (6) to which the drive force of the drive unit is transmitted via a rotating shaft (14), both being housed within a sealed container (2). The fluid machinery is provided with: an oil reservoir (76) in which lubricant is stored, on the inner bottom surface (2a) of the sealed container; and lubricating mechanisms (70, 72) which feed lubricant in the oil reservoir to the sliding parts of the drive unit and the driven unit by rotating in an integrated manner with a rotating shaft. The sealed container has a blocking part (90) on the inner sidewall (80d) thereof, which blocks the flow of lubricant in the peripheral direction on the inner sidewall.

Description

Fluid machinery

The present invention relates to a fluid machine, and more particularly to a fluid machine suitable for a hermetic reciprocating compressor that compresses a carbon dioxide refrigerant.

This type of fluid machine includes an airtight container, an electric compression element that is housed in the airtight container and includes a compression element (driven unit) and an electric element (drive unit), and an oil reservoir provided in the compression element. There is known a hermetic compressor including a suction pipe having one end connected to a compression element and the other end opened near a lubricating oil reservoir (see, for example, Patent Document 1).

JP-A-6-294380

In the above prior art, the crankshaft (rotary shaft) constituting the compression element is immersed in the lubricating oil stored in the inner bottom portion of the hermetic container and driven by the electric element so as to be provided in the crankshaft. Lubricating oil is sucked up by the mechanism and lubricated to the sliding portion of the compression element.
Here, since the oil supply mechanism is rotationally driven by the electric element, the lubricating oil in the oil reservoir is scattered in a parabolic shape in the sealed container by the rotation of the oil supply mechanism when sucked up. Further, the lubricating oil is discharged from the rotating crankshaft into the sealed container, and the discharged lubricating oil scatters in a parabolic shape in the sealed container.

The lubricating oil thus scattered in the sealed container adheres to the inner wall of the sealed container and flows so as to circulate in the circumferential direction of the sealed container along the inner wall. The time required for the lubricating oil to scatter and flow down to the oil reservoir and be stored becomes longer as the initial velocity at which the lubricating oil is scattered is larger and the viscosity force of the lubricating oil is larger.
Specifically, depending on the specifications of the compressor 1, the crankshaft and thus the oil pipe may rotate at about 3000 rpm, so the initial speed at which the lubricating oil is scattered increases in this case.

In the case of a hermetic compressor, particularly a hermetic compressor using a carbon dioxide refrigerant as the working fluid, refrigeration oil having a higher viscous force than conventional products is often used. Tend to be longer. Further, when the compressor is small and the maximum amount of lubricating oil stored in the oil reservoir is a small amount of about 200 cc, for example, if the required time is long, the amount of lubricating oil stored in the oil reservoir is reduced. It may decrease temporarily temporarily, and in the worst case, the amount of oil stored in the oil sump may temporarily become zero.

In such a state, the oil supply mechanism does not function as an idle operation, and it is not possible to properly supply oil to each sliding part of the drive unit and the driven unit, and the lubrication performance of the compressor is significantly reduced. Problems arise.
The present invention has been made based on the above-described circumstances, and an object of the present invention is to provide a fluid machine that can improve lubrication performance and improve reliability.

In order to achieve the above object, a fluid machine of the present invention is a fluid machine in which a drive unit and a driven unit to which the driving force of the drive unit is transmitted via a rotating shaft are accommodated in an airtight container. And an oil reservoir for storing the lubricating oil in the inner bottom portion of the sealed container, and an oil supply for supplying the lubricating oil in the oil reservoir to each sliding portion of the drive unit and the driven unit by rotating integrally with the rotating shaft. The airtight container has a shielding portion that shields the flow of the lubricating oil in the circumferential direction on the inner side wall (Claim 1).

Specifically, the shielding portion projects from the inner wall toward the oil sump portion (claim 2).
Further, a frame that supports the drive unit and the driven unit is provided, and the frame is fixed to the shielding portion.
Further, the sealed container is configured to include a bottom shell to be forged, the shielding portion is collectively formed when the bottom shell is forged (Claim 4), and the oil sump is formed when the bottom shell is forged. It is molded in a lump (claim 5).

Further, the shielding part has a wave shape continuously bulging toward the oil sump part (Claim 6), and a plurality of shielding parts are provided (Claim 7).
Furthermore, the pressure of the working fluid sucked into the driven unit and discharged from the driven unit acts in the sealed container, and the working fluid is a carbon dioxide refrigerant.

According to the fluid machine of the first and second aspects of the present invention, by having the shielding part, the lubricating oil scattered in the sealed container directly collides with the shielding part or directly collides with the shielding part. Even if it does not, it is greatly decelerated by exceeding the shielding part when it begins to circulate along the inner wall after adhering to the inner wall. The decelerated lubricating oil immediately flows down to the oil reservoir without continuing to circulate along the inner wall, greatly increasing the time required for the lubricating oil to flow down to the oil reservoir and be stored. Can be shortened. Therefore, even when the fluid machine is operated at high speed, the viscosity of the lubricating oil is large, and the maximum amount of oil stored in the oil reservoir is small, the circulation efficiency of the lubricating oil can be increased, and the lubrication of the fluid machine The performance can be improved.

According to invention of Claim 3, since a shielding part can be utilized as a base part for fixing a flame | frame to an airtight container by fixing a flame | frame to a shielding part, another site | part and another member are required. The frame can be fixed to the sealed container without any problems, and the productivity of the fluid machine can be improved.
According to the fourth aspect of the present invention, the shielding portion can be easily formed without requiring a separate member or a separate process by forming the shielding portion all together at the time of forging the bottom shell. The productivity of the machine can be improved.

According to the fifth aspect of the present invention, the oil sump portion can be formed easily at the time of the forging molding of the bottom shell, so that the oil sump portion can be easily formed without requiring a separate member or separate processing. The productivity of the fluid machine can be improved.
According to the sixth aspect of the invention, the shielding portion has a wave shape that continuously bulges toward the oil sump portion side, so that the scattered lubricating oil has one bulging of the shielding portion. Compared to the case, the probability of directly colliding with the shielding part is increased, or even when not directly colliding with the shielding part, it exceeds the shielding part when attached to the inner side wall and starts to circulate along the inner side wall. The number of times increases. Therefore, the lubricating oil can be decelerated more effectively, and the time required for the lubricating oil to flow down to the oil sump and be stored can be further shortened. Even when the viscosity of the lubricating oil is large and the maximum amount of oil stored in the oil reservoir is small, the circulation efficiency of the lubricating oil can be further increased and the lubricating performance of the fluid machine can be further improved. Can do.

According to the invention of claim 7, by providing a plurality of shielding portions, the scattered lubricating oil has a higher probability of directly colliding with the shielding portion than when there is one shielding portion, Or even if it does not directly collide with the shielding part, the number of times exceeding the shielding part increases when it starts to circulate along the inner wall after adhering to the inner wall. Therefore, the lubricating oil can be decelerated more effectively, and the time required for the lubricating oil to flow down to the oil sump and be stored can be further shortened. Even when the viscosity of the lubricating oil is large and the maximum amount of oil stored in the oil reservoir is small, the circulation efficiency of the lubricating oil can be further increased and the lubricating performance of the fluid machine can be further improved. Can do.

According to the eighth aspect of the present invention, when the working fluid is carbon dioxide refrigerant, the pressure of the working fluid discharged from the driven unit is increased to a supercritical state, and the temperature inside the fluid machine is high. Uses high-viscosity lubricating oil to prevent oil film breakage due to viscosity drop at high temperatures. However, when the temperature inside the fluid machine is low, the viscosity of the lubricating oil is large, and thus the scattered lubricating oil tends to hardly return. However, according to the above configuration, even when the lubricating oil has a high viscosity and the scattered lubricating oil tends to hardly return, the lubricating oil circulation efficiency can be increased and the lubrication performance of the fluid machine can be improved. It is preferable.

It is a longitudinal cross-sectional view of the compressor of 1st Example. It is a principal part enlarged view of the compression mechanism of FIG. It is the external view which showed the airtight container of the compressor of FIG. It is the perspective view which looked at the bottom shell of FIG. 3 from upper direction. FIG. 5 is a plan view showing a lubricating oil flow path in the bottom shell of FIG. 4 from above.

1 to 5 show a compressor 1 as a fluid machine of a first embodiment.
The compressor 1 is a hermetic reciprocating compressor, and is categorized in detail as a positive displacement compressor called a reciprocating compressor or a piston compressor. For example, a configuration of a refrigeration cycle (not shown) incorporated in a vending machine. Used as equipment.
The refrigeration cycle includes a path through which a refrigerant as a working fluid of the compressor 1 circulates. For example, a carbon dioxide refrigerant that is a non-flammable natural refrigerant is used as the refrigerant.

As shown in FIG. 1, the compressor 1 includes an airtight container 2, and an electric motor (drive unit) 4 and a compression mechanism (driven unit) to which the driving force of the electric motor 4 is transmitted are enclosed in the airtight container 2. 6) is housed.
The electric motor 4 includes a stator 8 that generates a magnetic field by power feeding and a rotor 10 that rotates by the magnetic field generated by the stator 8. The rotor 10 is disposed coaxially inside the stator 8, and will be described later. The main shaft portion 24 is fixed by shrinkage fitting. Electric power is supplied to the stator 8 from the outside of the compressor 1 through an electrical component 12 fixed to the sealed container 2 and a lead wire (not shown).

The compression mechanism 6 includes a crankshaft 14, a cylinder block 16, a piston 18, a connecting rod 20, and the like. The crankshaft 14 includes an eccentric shaft portion 22 and a main shaft portion 24.
As shown in FIG. 2, a cylinder bore 26 is formed integrally with the cylinder block 16, and a cylinder gasket 28, a later-described suction valve 50, and a valve plate 30 are sequentially arranged from the cylinder block 16 side so as to close the opening of the cylinder bore 26. The head gasket 32 and the cylinder head 34 are pressed and fixed by bolts.

As shown in FIG. 1, the stator 8 is bolted to the cylinder block 16 via a frame 36, and the frame 36 is fixed to the sealed container 2.
Specifically, the electric motor 4 and the compression mechanism 6 are supported by a pedestal portion 38 below the frame 36, and the frame 36 is fixed to the sealed container 2 by the pedestal portion 38. On the other hand, in the upper cylindrical portion 40 of the frame 36, the bearing 42 of the main shaft portion 24 is disposed on the inner peripheral surface 40a, and the thrust trace (bearing) that receives the thrust load of the rotor 10 on the upper end surface 40b of the cylindrical portion 40. Alternatively, a bearing 44 such as a thrust washer is disposed.

As shown in FIG. 2, the valve plate 30 includes a refrigerant suction hole 46 and a discharge hole 48, both of which are opened and closed by a suction valve 50 and a discharge valve 52, which are reed valves, respectively. The
The cylinder head 34 includes a refrigerant suction chamber 54 and a discharge chamber 56. When the discharge valve 52 is opened in the compression stroke of the piston 18, the discharge chamber 56 communicates with the cylinder bore 26 through the discharge hole 48. On the other hand, when the intake valve 50 is opened during the intake stroke of the piston 18, the intake chamber 54 communicates with the cylinder bore 26 via the intake hole 46.

A suction pipe 58 and a discharge pipe 60 are fixed to the sealed container 2, and one ends of the suction and

discharge pipes

58 and 60 are connected to a suction chamber 54 and a discharge chamber 56 of the cylinder head 34, respectively. The other ends of the suction and

discharge pipes

58 and 60 are connected to a refrigeration cycle via a suction muffler and a discharge muffler (not shown), and these mufflers reduce the pulsation and noise of the refrigerant flowing between the compressor 1 and the refrigeration cycle. ing.

The connecting rod 20 is provided with a large end 62 to which the eccentric shaft portion 22 of the crankshaft 14 is rotatably connected at one end, and a small end 64 to which the piston 18 is reciprocally connected at the other end. It has been. The small end portion 64 is connected to the piston 18 by a piston pin 66, and the piston pin 66 is secured to the piston 18 by a fixing pin 68.

When the crankshaft 14 rotates in this state, the connecting rod 20 swings in conjunction with the eccentric rotation of the eccentric shaft portion 22 with the piston pin 66 as a fulcrum, and the piston 18 interlocks with the swinging motion of the connecting rod 20. It reciprocates in the cylinder bore 26.
The suction pressure of the refrigerant mainly acts in the sealed container 2, and a small amount of lubricating oil for lubricating the sliding portions of the electric motor 4 and the compression mechanism 6 such as the

bearings

42 and 44 is present in the inner bottom portion 2 a of the sealed container 2. Stored.

In the crankshaft 14, an oil passage (oil supply mechanism) 70 is drilled from the substantially axial position of the lower end surface 22 a of the eccentric shaft portion 22 to the middle of the main shaft portion 24. An upper portion of the oil passage 70 is opened from the outer peripheral surface 24 a of the main shaft portion 24, and an oil pipe (oil supply mechanism) 72 is connected to the lower portion of the oil passage 70. The oil pipe 72 has an inclined portion 74 which is inclined from the substantially axial center of the eccentric shaft portion 22 toward the axial center of the main shaft portion 24 on the distal end side. It extends to the oil reservoir 76 having a concave shape in sectional view formed in the inner bottom 2a.

The oil sump portion 76 is formed to have a size and depth that allow a small amount of lubricating oil, for example, about 200 cc, to be stored so that the oil level is higher than the tip position of the oil pipe 74. When the oil pipe 72 rotates eccentrically together with the eccentric shaft portion 22 as the crankshaft 14 rotates, a centrifugal force acts on the lubricating oil in the inclined portion 74 in the oil pipe 72 in an obliquely upward outward direction. Is pumped from the oil reservoir 76 to the oil passage 74. Further, along with the eccentric rotation of the oil pipe 72, a part of the lubricating oil in the oil reservoir 76 is scattered in a parabolic shape in the sealed container 2.

Hereinafter, the operation and action of the compressor 1 will be described.
In the compressor 1, the rotor 10 fixed to the main shaft portion 24 is rotated by supplying power to the stator 8, and consequently the crankshaft 14 is rotated, and the piston 18 reciprocates in the cylinder bore 26 via the connecting rod 20. The reciprocating motion of the piston 18 causes the refrigerant to be sucked into the cylinder bore 26 from the refrigeration cycle, and the refrigerant is compressed by the cylinder bore 26 and further discharged to the refrigeration cycle.

Specifically, when the piston 18 operates in the direction of decreasing the volume of the cylinder bore 26 and the refrigerant in the cylinder bore 26 is compressed and the pressure in the cylinder bore 26 exceeds the discharge pressure of the refrigerant, the pressure in the cylinder bore 26 and the discharge chamber 56 are increased. The discharge valve 52 opens due to the difference from the internal pressure. The compressed refrigerant is guided to the discharge chamber 56 via the discharge hole 48 and discharged to the refrigeration cycle via the discharge pipe 60.

Next, when the operation of the piston 18 changes from the top dead center in a direction in which the volume in the cylinder bore 26 increases, the pressure in the cylinder bore 26 decreases. When the pressure in the cylinder bore 26 decreases, the discharge valve 52 closes according to the difference between the pressure in the cylinder bore 26 and the pressure in the discharge chamber 56.
When the pressure in the cylinder bore 26 becomes equal to or lower than the suction pressure of the refrigerant, the suction valve 50 opens according to the difference between the pressure in the cylinder bore 26 and the pressure in the suction chamber 54. The refrigerant in the refrigeration cycle is guided to the suction chamber 54 through the suction pipe 58 and is sucked into the cylinder bore 26 through the suction hole 46.

Next, when the operation of the piston 18 changes from the bottom dead center in a direction in which the volume in the cylinder bore 26 decreases, the refrigerant in the cylinder bore 26 is compressed again. In this way, a series of processes of sucking the refrigerant from the refrigeration cycle into the cylinder bore 26, compressing the refrigerant in the cylinder bore 26, and discharging the refrigerant to the refrigeration cycle is repeated.

The lubricating oil pumped up from the oil reservoir 76 to the oil passage 70 in accordance with the operation of the compressor 1 described above flows out of the oil passage 70, and the discharged lubricating oil is scattered in a parabolic shape in the sealed container 2. . The scattered lubricating oil flows down to the eccentric shaft portion 22 side and lubricates the vicinity of the large end portion 62. Further, the lubricating oil is scattered toward the piston 18 by the flange portion 22b formed on the eccentric shaft portion 22, and lubricates the vicinity of the skirt portion 18a of the piston 18.

On the other hand, a part of the lubricating oil flowing out from the oil passage 70 rises along an outer peripheral groove (not shown) formed in the crankshaft 14 by centrifugal force, and forms an oil film between the crankshaft 14 and the frame 36. Then, the bearing 42 is lubricated and moved to the upper end side of the crankshaft 14. The lubricating oil reaches the upper end surface 40b of the cylindrical portion 40 and lubricates the bearing 44, and then flows down to the oil sump portion 76 by gravity. On the other hand, the lubricating oil that cannot pass through the bearing 44 rises as it is up the inner wall surface 10a of the rotor 10 to the upper end of the rotor 10, is scattered by the centrifugal force due to the rotation of the rotor 10, cools the stator 8, and then To flow down to the oil sump 76.

The oil mist sucked into the cylinder bore 26 when lubricating the vicinity of the skirt portion 18a of the piston 18 enters the gap between the piston 18 and the cylinder block 16 together with the refrigerant gas leaked from the cylinder bore 26, and seals and lubricates the piston 18. I do. At this time, the lubricating oil adhering to the wall surface 54a of the suction chamber 54 flows down to the oil reservoir 76 due to gravity. The lubricating oil that has flowed down to the oil reservoir 76 in this manner is pumped up again from the oil pipe 72 and contributes to the lubrication and sealing of the sliding portions of the electric motor 4 and the compression mechanism 6 as described above, and the sealed container 2. Circulate inside.

By the way, in this embodiment, as shown in FIG. 3, the sealed container 2 is composed of two shells, a top shell 78 covering the electric motor 4 side and a bottom shell 80 covering the compression mechanism 6 side. It has a structure. Since the crankshaft 14 and the connecting rod 20 are positioned so as to be substantially orthogonal within the sealed container 2, the longitudinal direction of the electric motor 4 is accommodated in the depth direction of the top shell 78, and the top shell 78 is the bottom shell 80. Compared to, it has a deep bottom shape. On the other hand, the compression mechanism 6 is accommodated in the radial direction of the bottom shell 80 in the longitudinal direction, and the bottom shell 80 has a shallow bottom shape as compared with the top shell 78.

Each of the

shells

78 and 80 has root edges protruding from the respective

open end portions

78a and 80a, and the groove portions 82 are formed by abutting each root edge with each other. Each of the

shells

78 and 80 is joined by forming a bead-shaped welded portion 84 continuous around the entire circumference of the groove portion 82 by a single welding operation, that is, a single butt formed by a single welding operation. Joined with welded joints.

The bottom shell 80 is formed by forging, and has a gripping portion 86 that is gripped during the forging molding. The gripping portion 86 protrudes from the outer top portion 80c of the bottom shell 80 at the radial center side with respect to the side portion 80b of the bottom shell 80. Is done. The oil sump portion 76 is recessed at the position of the inner bottom portion 2a on the back side of the gripping portion 86 so as to be substantially similar to the outer shape of the gripping portion 86. That is, the bottom shell 80 is formed from the side portion 80b to the outer top portion 80c with substantially the same thickness as the side portion 80b.

A base plate 88 for stably mounting the compressor 1 is attached around the gripping portion 86 of the outer top portion 80c. By attaching anti-vibration rubber (not shown) to the lower surface of the base plate 88, the compressor 1 can be fixed while suppressing vibration during operation.
Here, as shown in FIG. 4, in this embodiment, the inner wall 80 d near the opening end 80 a of the bottom shell 80 swells toward the radial center of the bottom shell 80, that is, toward the oil reservoir 76. A shielding portion 90 for the lubricating oil that has been discharged is formed. The shielding portion 90 has a wave shape that is continuously bulged twice toward the oil sump portion 76 side, and two shield portions 90 are provided facing the position where the oil sump portion 76 is sandwiched between the bottom shell 80 as viewed from above. It has been.

A frame 36 that supports the stator 8 and the cylinder block 16 shown in FIG. 1 is fixed to the upper surface 90 a of the shielding portion 90. The shielding portion 90 also has a function as a pedestal portion for fixing the frame 36 to the sealed container 2. is doing.
As described above, the gripping portion 86, the oil sump portion 76, and the shielding portion 90 formed on the bottom shell 80 are all formed at the same time when the bottom shell 80 is forged.

In the compressor 1 of the first embodiment described above, the lubricating oil scattered by the rotation of the oil pipe 72 rotated in the clockwise direction when viewed from above, for example, in the closed shell 2, particularly in the bottom shell 80, Lubricating oil scattered by the release from the oil passage 70 or the collision with the flange 22 b adheres to the inner wall 80 d of the bottom shell 80. The lubricating oil tends to flow so as to circulate in the circumferential direction of the bottom shell 80 along the inner wall 80d.

However, as indicated by an arrow in FIG. 5, due to the presence of the shielding portion 90, (a) the scattered lubricating oil collides directly with the (b) shielding portion 90 or directly with the shielding portion 90. Even if not, (c) when moving on the inner wall 80d and starting to circulate along the inner wall 80d, the moving speed is greatly reduced by exceeding the shielding portion 90. The decelerated lubricating oil immediately flows down to (d) the oil reservoir 76 without continuing to circulate along the inner wall 80d. As a result, the required time T from when the lubricating oil is scattered until it flows down to the oil reservoir 76 and is stored can be significantly reduced.

In particular, the required time T becomes longer as the initial velocity v at which the lubricating oil is scattered is larger and the viscous force of the lubricating oil is larger. Furthermore, when the compressor 1 is small and the maximum oil storage amount of the oil reservoir 76 is a small amount of about 200 cc as described above, if the required time T is long, the oil storage amount of the oil reservoir 76 is reduced. The oil supply mechanism may be reduced to a temporary state and may be zero in the worst case, and the oil supply mechanism will not function as an idle operation, so that each sliding part of the electric motor 4 and the compression mechanism 6 is appropriately supplied with oil. This causes a problem that the lubrication performance of the compressor 1 is remarkably deteriorated.

However, in this embodiment, even when the compressor 1 is operated at a high speed in this way, the viscosity of the lubricating oil is large, and the maximum oil storage amount of the oil reservoir 76 is small, the lubricating oil circulation efficiency is high. The lubricating performance of the compressor 1 can be improved.
Further, since the frame 36 is fixed to the shielding portion 90, the shielding portion 90 can be used as a pedestal portion for fixing the frame 36 to the sealed container 2, so that the frame can be used without requiring a separate part or member. 36 can be fixed to the airtight container 2, and the productivity of the compressor 1 can be improved.

Further, the shielding portion 90 and the oil sump portion 76 are formed at the same time when the bottom shell 80 is forged, thereby easily forming the shielding portion 90 and the oil sump portion 76 without requiring separate members or processing. And the productivity of the compressor 1 can be improved.
Furthermore, the shielding portion 90 has a wave shape that is continuously swollen twice toward the oil sump portion 76 side. Further, by providing two shielding portions 90, the scattered lubricating oil Compared to the case where there is only one bulge and the case where there is only one shielding part 90, the probability of directly colliding with the shielding part 90 is increased, or directly to the shielding part 90. Even when the collision does not occur, the number of times exceeding the shielding portion 90 increases when it adheres to the inner wall 80d and starts to circulate along the inner wall 80d. Accordingly, the lubricating oil can be decelerated more effectively, and the required time T from when the lubricating oil is scattered until it flows down to the oil reservoir 76 and stored can be further shortened. Is operated at high speed, the viscosity of the lubricating oil is large, and even when the maximum oil storage amount of the oil reservoir 76 is small, the circulation efficiency of the lubricating oil can be further increased, and the lubricating performance of the compressor 1 can be improved. Can be further improved.

The present invention is not limited to the above-described embodiments, and various modifications can be made.
Specifically, the shielding portion is not limited to a shape that protrudes toward the oil reservoir 76 on the inner wall 80d as in the shielding portion 90 of the present embodiment, and the circumferential portion of the inner wall 80d is not limited. Various shapes and installation numbers are conceivable as long as the lubricating oil can be decelerated by blocking the smooth flow of the lubricating oil and guided to the oil reservoir 76. Specifically, a thing like a shielding plate may be provided on the inner wall 80d, or a part of the inner wall 80d may be recessed in a wave shape. Also, jagged irregularities may be provided in the circumferential direction of the inner wall 80d, or stepped irregularities may be provided in the circumferential direction of the inner wall 80d.

Further, although the working fluid of the compressor 1 of the present embodiment is a carbon dioxide refrigerant, it is not limited to this. However, when the working fluid is carbon dioxide refrigerant, the pressure of the working fluid discharged from the compression mechanism 6 becomes high to the supercritical state, and the temperature inside the compressor 1 becomes high, so that the viscosity is relatively high. Lubricating oil is used to prevent oil film breakage due to low viscosity at high temperatures. However, when the temperature inside the compressor 1 is low, the viscosity of the lubricating oil is high, and therefore the scattered lubricating oil tends to be difficult to return. However, according to the above configuration, the lubricating oil circulation efficiency can be increased and the lubricating performance of the compressor 1 can be improved even if the lubricating oil has a large viscosity and the scattered lubricating oil tends to hardly return. This is preferable.

Furthermore, although the present Example demonstrates the positive displacement compressor 1, this invention is applicable to general sealed fluid machines, such as a scroll compressor and an expander, These fluid machines are other than a vending machine. Of course, it can be used as a component device of the refrigeration cycle incorporated in the.

1 Compressor (fluid machine)
2 Sealed container 2a Inner bottom 4 Electric motor (drive unit)
6 Compression mechanism (driven unit)
14 Crankshaft (Rotating shaft)
36 frame 70 oil passage (oil supply mechanism)
72 Oil pipe (oil supply mechanism)
76 Oil sump 80 Bottom shell 80d Inner wall 90 Shield

Claims

A fluid machine in which a driving unit and a driven unit to which the driving force of the driving unit is transmitted via a rotating shaft are housed in an airtight container,
An oil sump for storing lubricating oil in the inner bottom of the sealed container;
An oil supply mechanism that supplies the lubricating oil in the oil reservoir to each sliding part of the drive unit and the driven unit by rotating integrally with the rotary shaft;
The fluid container according to claim 1, wherein the sealed container has a shielding portion that shields a flow of lubricating oil in a circumferential direction on the inner wall on the inner wall.
2. The fluid machine according to claim 1, wherein the shielding portion protrudes toward the oil reservoir portion on the inner wall.
A frame for supporting the drive unit and the driven unit;
The fluid machine according to claim 2, wherein the frame is fixed to the shielding part.
The sealed container includes a bottom shell to be forged,
The fluid machine according to claim 3, wherein the shielding portion is formed in a lump when the bottom shell is forged.
5. The fluid machine according to claim 4, wherein the oil sump portion is formed in a lump when the bottom shell is forged.
6. The fluid machine according to claim 5, wherein the shielding part has a wave shape continuously bulging toward the oil sump part side.
The fluid machine according to any one of claims 1 to 6, wherein a plurality of the shielding portions are provided.
8. The working fluid is sucked into the driven unit and discharged from the driven unit in the sealed container, and the working fluid is a carbon dioxide refrigerant. The fluid machine according to any one of the above.