JPH08144955A - Sealed motor-driven compressor - Google Patents

Abstract

PURPOSE: To solve a forming-related problem by laying a bypass pipeline with a float valve section at one end to house a float valve, with the float valve section positioned on the bottom of a sealed vessel. CONSTITUTION: A bypass pipeline 15 having a float valve section 17 at one end to house a float valve 16, is provided so that the section 17 is positioned on the bottom of a sealed vessel 9, and the other end of the pipe line 15 is connected to a refrigerant intake pipeline 7. The specific gravity of the valve 16 is set at a value less than the specific gravity of a refrigerant 13, but larger than the specific gravity of lubricating oil 14. When an electric motor is stopped, the refrigerant 13 is liquefied and two liquid layers are formed on the bottom of the vessel 9 out of the liquefied refrigerant 13 as a lower layer and the lubricating oil 14 as an upper layer. As a result, the float valve 16 becomes afloat to open the pipeline 15. In this state, when the motor is started and pressure in the vessel 9 drops, the refrigerant 13 enters the section 17 via a hole 18, and flows to the pipeline 7 via the bypass pipeline 15. According to this construction, no forming-related problem occurs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic electric compressor, and more particularly, to an HFC-based refrigerant that does not have a risk of depleting the ozone layer and an incompatible or compatible HFC-based refrigerant. The present invention relates to a hermetic electric compressor that solves the problem of forming when a small amount of lubricating oil such as mineral oil is used.

[0002]

2. Description of the Related Art Dichlorodifluoromethane (R-12) and azeotrope mixed refrigerants R-12 and 1,1-difluoroethane (R-) have hitherto been used as refrigerants for refrigerators.
152a) and many R-502s. These refrigerants are suitable for ordinary refrigeration equipment, and CF such as R-12 is used.
Refrigeration cycles using refrigerating machine oils such as mineral oils and alkylbenzene-based oils that are compatible with C-based refrigerants have reached high quality levels such as reliability and durability.

[0003] However, each of the above refrigerants, due to its high ozone depletion potential, destroys the ozone layer when it is released into the atmosphere and reaches the ozone layer above the earth. The destruction of the ozone layer is caused by chlorine groups (Cl) in the refrigerant. Therefore, a refrigerant with a low chlorine group content, such as chlorodifluoromethane (HCFC-22,
R-22), a refrigerant containing no chlorine group, such as difluoromethane (HFC-32, R-32), pentafluoroethane (HFC-125, R-125), 1,1,1,2
-Tetrafluoroethane (HFC-134a, R-13
4a), or mixtures thereof, are considered as alternative refrigerants for these.

Refrigerating machine oils used for these HFC-based refrigerants are mineral oils or alkylbenzene-based oils that are incompatible or less compatible with HFC-based refrigerants, or HFC-based refrigerants, etc. Examples include ester-based lubricating oils, ether-based lubricating oils, and mixed oils thereof that are compatible with the refrigerant.

FIG. 7 shows an example of a refrigeration circuit of a refrigeration system. 1
Is a hermetic electric compressor that sucks the vaporized refrigerant from the suction pipe line 7, compresses it, and discharges it from the discharge pipe line 8 to the condenser.
Is a condenser for condensing and liquefying the refrigerant, 3 is a dryer filled with a desiccant for removing water in the refrigeration circuit, 4 is a capillary tube for reducing the pressure of the refrigerant, 5 is an evaporator for evaporating the liquefied refrigerant, and 6 Indicates the accumulator, and the arrow indicates the flow direction of the refrigerant.

FIG. 6 is a sectional explanatory view of a conventional hermetic electric compressor 1. Reference numeral 9 denotes a hermetic container, and in the container, a compression unit 11 arranged on the upper side and an electric motor unit 12 arranged on the lower side.
And are stored. The compression unit 11 and the electric motor unit 12 are elastically attached to the inner wall of the closed container 9 via a support device (not shown). The refrigerant sucked from the suction pipeline 7 is sucked from the suction section 10, compressed by the compression section 11 and discharged from the discharge pipeline 8 to the condenser.

Lubricating oil 14 contained in the bottom of the closed container 9
Is sucked up by a vacuum phenomenon due to a vortex flow formed at an upper open end by high-speed rotation of a rotating shaft (not shown) of the electric motor unit 12, and a self-lubricating unit (not shown) is configured to circulate and lubricate each mechanical motion unit. ing.

In the conventional hermetic electric compressor 1 shown in FIG. 6, when a refrigerant such as HFC is used and a lubricating oil such as mineral oil which is incompatible with the refrigerant or has a low compatibility is used, When the electric motor (not shown) is stopped, the refrigerant is liquefied, and since the specific gravity of the liquefied refrigerant 13 is larger than that of the lubricating oil 14, the liquefied refrigerant 13 is the lower layer and the lubricating oil 14 is the upper layer at the bottom of the closed container 9. Two layers are formed.

As an example of the specific gravity, for example, the specific gravity of the alkylbenzene oil as the lubricating oil is about 0.9, and the specific gravity of the refrigerant HFC-134a is about 1.20.

When the electric motor (not shown) is started in this state, the pressure in the closed container 9 drops and the lower layer refrigerant 13
Rapidly becomes vaporized and the refrigerant and the lubricating oil 14 are mixed with each other to form a foam (forming), which pushes up the compression section 11 and the electric motor section 12 to collide with the inner wall of the hermetic container 9 and make a loud noise. In addition to causing a problem such as deformation, the refrigerant 13 and the lubricating oil 14 are sucked into the suction portion 10 in a mixed state and compressed and discharged from the discharge pipe line 8. There is a problem of lack of lubrication (hereinafter referred to as forming problem).

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to use a HFC-based refrigerant or a refrigerant mainly composed of an HFC-based refrigerant as a refrigerant, and use a lubricating oil that is incompatible or less compatible with the refrigerant. An object of the present invention is to provide a hermetic electric compressor that solves the problem of forming when using.

[0012]

As a result of repeated studies to solve the above problems, the present inventors have found that the above problems can be solved by providing a specific bypass pipe line in a closed container of a compressor. The present invention has been completed.

According to the first aspect of the present invention, H is used as the refrigerant.
Uses a FC-based or HFC-based refrigerant as the main component, and uses a lubricating oil that is incompatible with the refrigerant or has little compatibility as the lubricating oil, and compresses the lubricating oil stored in the bottom of the closed container with the electric motor part. Circulate and lubricate the mechanical movement part of the
In a hermetic electric compressor that compresses and discharges refrigerant sucked by a compression unit connected to an electric motor unit, a bypass pipe line provided with a float valve unit having a built-in float valve at one end and a float valve unit at the bottom of a hermetic container In the hermetic electric compressor, the other end of the float valve is connected to the suction line of the refrigerant, and the specific gravity of the float valve is set smaller than the specific gravity of the refrigerant and larger than the specific gravity of the lubricating oil. is there.

According to the second aspect of the present invention, H is used as the refrigerant.
Uses a FC-based or HFC-based refrigerant as the main component, and uses a lubricating oil that is incompatible with the refrigerant or has little compatibility as the lubricating oil, and compresses the lubricating oil stored in the bottom of the closed container with the electric motor part. Circulate and lubricate the mechanical movement part of the
In a hermetic electric compressor that compresses and discharges refrigerant sucked by a compression unit connected to an electric motor unit, a bypass pipe line provided with a float valve unit having a built-in float valve at one end and a float valve unit at the bottom of a hermetic container , The other end of which is opened to the gas phase in the closed container, and the specific gravity of the float valve is set smaller than the specific gravity of the refrigerant and larger than the specific gravity of the lubricating oil. It is a machine.

According to a third aspect of the present invention, H is used as the refrigerant.
Uses a FC-based or HFC-based refrigerant as the main component, and uses a lubricating oil that is incompatible with the refrigerant or has little compatibility as the lubricating oil, and compresses the lubricating oil stored in the bottom of the closed container with the electric motor part. Circulate and lubricate the mechanical movement part of the
In a hermetic electric compressor that compresses and discharges a refrigerant sucked by a compression unit connected to an electric motor unit, a bypass pipe line whose both ends are open has one end at the bottom of the hermetic container and the other end inside the hermetic container. The hermetically-sealed electric compressor is provided so as to be located in a gas phase portion.

According to a fourth aspect of the present invention, in the hermetic electric compressor according to the first to third aspects, a plurality of bypass lines are provided.

According to a fifth aspect of the present invention, in the hermetic electric compressor according to the first to fourth aspects, the lubricating oil is a lubricating oil selected from mineral oils, alkylbenzene oils or mixtures thereof. Is characterized by.

[0018]

In the hermetic electric compressor according to the first aspect of the present invention, a bypass pipe line having a float valve portion containing a float valve at one end is provided, and the float valve portion is provided at the bottom of the hermetic container.
It is characterized in that the other end is provided so as to be connected to the suction line of the refrigerant, and the specific gravity of the float valve is set smaller than the specific gravity of the refrigerant and larger than the specific gravity of the lubricating oil.

When the electric motor is stopped, the refrigerant is liquefied, and two layers are formed at the bottom of the closed container, the liquefied refrigerant being the lower layer and the lubricating oil being the upper layer. However, when the electric motor is started in this state (hereinafter referred to as "sleep start") and the pressure in the closed container decreases, the float valve floats and the bypass line opens because the inside of the float valve section is filled with refrigerant. Therefore, the refrigerant in the lower layer flows through the bypass line to the suction line. Therefore, the problem of forming does not occur. When the liquefied refrigerant flows out from the bypass pipe line to the bottom of the closed container and substantially disappears, the inside of the float valve portion is filled with the lubricating oil, so that the float valve sinks and closes the bypass circuit. Since lubricating oil does not enter the bypass pipeline, the bypass pipeline operates in the same manner as above when starting to lie down next time, so that the problem of forming does not occur.

In the hermetic electric compressor according to the second aspect of the present invention, the above-mentioned bypass conduit is provided with a float valve portion at the bottom of the hermetic container and the other end opening to a gas phase portion in the hermetic container. It is characterized in that it is provided to do. At the start of sleeping, the bypass line acts in the same way as above, so there is no forming problem. Also, since no lubricating oil enters the bypass line, the forming problem does not occur at the next start of sleeping.

In the hermetic electric compressor according to the third aspect of the present invention, one end of the bypass pipe, which is open at both ends, is located at the bottom of the hermetic container, and the other end is located at the gas phase in the hermetic container. It is characterized by being provided as follows. When the pressure in the closed container decreases at the start of sleeping, the refrigerant in the lower layer flows through the bypass pipe line to the vapor phase portion in the closed container and is vaporized, so that the problem of forming does not occur. The bypass line works in the same way at the next sleep start, so there is no forming problem.

The bypass conduits used in the present invention may be provided with a plurality of the same type, or a plurality of different types may be combined and provided.

The material of the float valve is stable with respect to the refrigerant and lubricating oil used, the float valve itself is not affected by the refrigerant and lubricating oil used, and the specific gravity of the float valve is the specific gravity of the refrigerant. There is no particular limitation as long as it can be set smaller and larger than the specific gravity of the lubricating oil. Specifically, for example, plastics, engineering plastics (polyamide, polyacetal, polycarbonate, modified polyphenylene ether, polybutylene terephthalate, polyphenylene sulfide, polyarylate, etc.), glass, metal, ceramics, etc., and compositions thereof, etc. Can be mentioned. The shape and size of the float valve are not particularly limited.

[0024]

EXAMPLES The contents of the present invention will be described in more detail below with reference to FIGS. 1 to 5, but the present invention is not limited to these contents.

FIG. 1 is a sectional explanatory view of the hermetic electric compressor of the present invention. The bypass pipe line 15 having a float valve portion 17 having a built-in float valve 16 at one end is connected to the float valve portion 1.
7 is arranged at the bottom of the closed container 9, and the other end is connected to the suction line 7 for the refrigerant. The specific gravity of the float valve 16 is set smaller than that of the refrigerant 13 and larger than that of the lubricating oil 14.

When the electric motor (not shown) is stopped, the refrigerant is liquefied, and two layers are formed at the bottom of the closed container 9 in which the liquefied refrigerant 13 is the lower layer and the lubricating oil 14 is the upper layer. Since the specific gravity of the float valve is set smaller than the specific gravity of the refrigerant 13, the float valve 16 floats in the float valve portion 17 filled with the refrigerant 13 as shown in FIG. 15 is open. When the electric motor is started in this state and the pressure in the closed container 9 drops, the refrigerant 13 flows from the hole 18 into the float valve portion 17 and flows through the bypass pipe line 15 into the suction pipe line 7, causing a problem of forming. Absent.

When the refrigerant 13 flows out of the bypass line 15 and substantially disappears at the bottom of the closed container 9, the specific gravity of the float valve is set to be larger than that of the lubricating oil 14.
As shown in FIG. 2A, the float valve 16 sinks in the float valve portion 17 filled with the lubricating oil 14 to close the bypass circuit 15. Therefore, since the lubricating oil 14 does not enter the bypass pipeline 15, the bypass pipeline 15 operates in the same manner as above even when the next bed start is started, so that the problem of forming does not occur.

FIG. 3 is a sectional view showing another hermetic electric compressor of the present invention. The bypass conduit 15A having the same structure as described above is provided so that the float valve portion 17 is arranged at the bottom of the closed container 9 and the other end opens to the gas phase portion 19 in the closed container 9. Bypass line 15 at the start of sleeping
Since A works in the same manner as in the above case, the problem of forming does not occur. Further, since the lubricating oil 14 does not enter the bypass pipe line 15A, the forming problem does not occur at the next start of sleeping.

FIG. 4 is a sectional explanatory view of another hermetic electric compressor according to the present invention. The bypass pipe line 15B having the same structure as described above is provided so that the float valve portion 17 is arranged at the bottom of the closed container 9 and the other end opens to the gas phase portion 19 in the closed container 9. Bypass line 15 at the start of sleeping
Since B acts in the same manner as in the above case, the problem of forming does not occur. Further, since the lubricating oil 14 does not enter the bypass line 15B, the forming problem does not occur at the next start of sleeping.

FIG. 5 is a sectional view showing another hermetic electric compressor of the present invention. Bypass line 15 with both ends open
C is provided so that one end is located at the bottom of the closed container 9 and the other end is located at the gas phase portion 19 in the closed container 9. When the pressure in the closed container 9 decreases at the start of sleeping, the lower layer refrigerant 13 flows through the bypass pipe line 15C to the vapor phase portion 19 in the closed container 9 and is vaporized, so that the problem of forming does not occur. Bypass line 1 at the start of the next sleep
5C works in the same way, so no forming problems occur.

[0031]

Since the hermetic electric compressor of the present invention is provided with a specific bypass pipe line in the hermetic container of the compressor, a refrigerant such as an HFC system which does not cause a danger of destroying the ozone layer is used, and the HFC system is used. Even when using a lubricating oil that is incompatible with the refrigerant or has a low compatibility with the refrigerant, there is no problem of forming at the start of sleeping, and stable operation can be performed for a long time. The hermetic electric compressor of the present invention is economical because it has a simple structure, and has a great effect, so that it has a high industrial utility value.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view of a hermetic electric compressor of the present invention.

FIG. 2 is an enlarged cross-sectional explanatory view of the vicinity of the float valve portion used in the present invention.

FIG. 3 is a cross-sectional explanatory view of another hermetic electric compressor of the present invention.

FIG. 4 is a cross-sectional explanatory view of another hermetic electric compressor of the present invention.

FIG. 5 is a cross-sectional explanatory view of another hermetic electric compressor of the present invention.

FIG. 6 is a cross-sectional explanatory view of a conventional hermetic electric compressor.

FIG. 7 is an example of a refrigeration circuit of a refrigeration system.

[Explanation of symbols]

 1 Hermetic Electric Compressor 2 Condenser 3 Dryer 4 Capillary Tube 5 Evaporator 6 Accumulator 7 Suction Pipeline 8 Discharge Pipeline 9 Sealing Container 10 Suction Part 11 Compressing Part 12 Electric Motor Part 13 Refrigerant 14 Lubricating Oil 15, 15A, 15B, 15C Bypass pipe 16 Float valve 16 17 Float valve part 18 Hole 19 Gas phase part

Claims (5)

[Claims] 1. An HFC-based refrigerant or HFC as a refrigerant
Using a refrigerant mainly composed of a system refrigerant and a lubricant oil that is incompatible or less compatible with the refrigerant as the lubricating oil, the lubricating oil stored in the bottom of the closed container is mechanically operated by the electric motor section and the compression section. In the hermetic electric compressor that circulates and lubricates the parts, and compresses and discharges the refrigerant sucked by the compression part that is connected to the electric motor part, a bypass pipe line provided with a float valve part containing a float valve at one end, The float valve is arranged at the bottom of the closed container, the other end is connected to the refrigerant suction pipe, and the specific gravity of the float valve is set to be smaller than the specific gravity of the refrigerant and larger than the specific gravity of the lubricating oil. A hermetic electric compressor. 2. An HFC-based refrigerant or HFC as the refrigerant
Using a refrigerant mainly composed of a system refrigerant and a lubricant oil that is incompatible or less compatible with the refrigerant as the lubricating oil, the lubricating oil stored in the bottom of the closed container is mechanically operated by the electric motor section and the compression section. In the hermetic electric compressor that circulates and lubricates the parts, and compresses and discharges the refrigerant sucked by the compression part that is connected to the electric motor part, a bypass pipe line provided with a float valve part containing a float valve at one end, The float valve portion is arranged at the bottom of the closed container, the other end is provided so as to open to the gas phase portion in the closed container, the specific gravity of the float valve is smaller than the specific gravity of the refrigerant,
A hermetic electric compressor characterized by having a specific gravity set higher than that of the lubricating oil. 3. An HFC type refrigerant or HFC as the refrigerant
Using a refrigerant mainly composed of a system refrigerant and a lubricant oil that is incompatible or less compatible with the refrigerant as the lubricating oil, the lubricating oil stored in the bottom of the closed container is mechanically operated by the electric motor section and the compression section. In a hermetic electric compressor that circulates and lubricates the compressor, and compresses and discharges the refrigerant sucked by the compressor that is connected to the electric motor part, the bypass pipe line that is open at both ends is connected to the bottom of the hermetic container. A hermetic electric compressor, wherein the other end is provided so as to be located in a gas phase portion in the hermetic container. 4. The hermetic electric compressor according to claim 1, wherein a plurality of bypass lines are provided. 5. The hermetic electric compressor according to claim 1, wherein the lubricating oil is a lubricating oil selected from mineral oils, alkylbenzene oils or mixtures thereof.