JP3619622B2 - Hermetic compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hermetic compressor, and more particularly to a hermetic compressor used in a refrigeration apparatus that uses an HFC-based refrigerant or the like that has no danger of destroying the ozone layer. O. The present invention relates to a hermetic compressor with improved P.
[0002]
[Prior art]
Conventionally, there are many R-502s composed of dichlorodifluoromethane (R-12), azeotropic refrigerant mixture R-22 and monochloropentafluoroethane (R-115a) as refrigerants for refrigerators. However, the above-mentioned refrigerant has high ozone destruction, and when it is released into the atmosphere and reaches the ozone layer over the earth, it destroys this ozone layer. This destruction of the ozone layer is caused by chlorine groups (Cl) in the refrigerant.
Accordingly, a refrigerant having a low chlorine group content, such as chlorodifluoromethane (HCFC-22, R-22), a refrigerant not containing a chlorine group, such as difluoromethane (HFC-32, R-32), pentafluoroethane. (HFC-125, R-125), 1,1,1,2-tetrafluoroethane (HFC-134a, R-134a) or a mixture of two or more of these (for example, R410A) can be substituted for these. It is considered as a refrigerant (hereinafter referred to as HFC refrigerant).
[0003]
In a conventional hermetic compressor of a type in which refrigerant compressed by a compression element is discharged into a sealed container from a plurality of discharge ports, the top clearance volume (V) of each discharge port is the same. However, since the flow path resistance of the refrigerant discharged from the discharge port into the sealed container varies depending on the position and arrangement of each discharge port, any of the C.V. O. It has been difficult to design such that P can be improved.
[0004]
[Problems to be solved by the invention]
An object of the present invention is a hermetic compressor used in a refrigeration apparatus using an HFC-based refrigerant or the like that has no danger of destroying the ozone layer, O. It is to provide a hermetic compressor with improved P.
[0005]
[Means for Solving the Problems]
As a result of repeated studies to solve the above problems, the present inventors have determined that the top clearance volume of the discharge port having the larger flow path resistance of the refrigerant discharged from the discharge port into the sealed container is the flow path of the same refrigerant. By determining the top clearance volume so that the sum of these top clearance volumes is expressed by a specific empirical formula, by making it larger than the top clearance volume of the discharge port with the smaller resistance, It has been found that the above problems can be solved, and the present invention has been completed.
[0006]
According to the first aspect of the present invention, an electric element having a rotating shaft on the upper side and a compression element driven by the rotating shaft of the electric element on the lower side are accommodated, and the sucked refrigerant is compressed by the compression element. A hermetic compressor that is discharged into the hermetic container and then discharged out of the hermetic container, and the compression element includes a cylinder having a suction port and an eccentric portion of the rotary shaft. A rotating roller, a vane that contacts the roller and divides the inside of the cylinder, an upper bearing portion and a lower bearing portion that seal the opening of the cylinder, and a plurality of discharge ports including discharge valves provided in these bearing portions; In a hermetic compressor composed of a cup muffler covering these discharge valves, the top clearance volume of the discharge port having the larger flow path resistance of the refrigerant discharged from the discharge port into the sealed container. The (VA), is a hermetic compressor, characterized in that larger than top clearance volume of the discharge port towards the flow path resistance of the refrigerant is small (Va) (VA> Va).
[0007]
According to a second aspect of the present invention, an electric element having a rotating shaft on the upper side and a plurality of compression elements driven by the rotating shaft of the electric element on the lower side are accommodated, and the sucked refrigerant is absorbed by the compression element. A hermetic compressor that is compressed and discharged into a sealed container and then discharged out of the sealed container, and each of the plurality of compression elements includes a cylinder having a suction port and the rotating shaft. A roller that rotates in the cylinder by an eccentric part, a vane that contacts the roller and separates the inside of the cylinder, an upper bearing part that seals the opening of the upper cylinder, a lower bearing part that seals the opening of the lower cylinder, and the upper bearing part Consists of an upper discharge port with a discharge valve, a cup muffler covering the discharge valve, a lower discharge port with a discharge valve provided in the lower bearing, and a cup muffler covering the discharge valve In the closed type compressor, the top clearance volume (V2) of the lower discharge port is made larger than the top clearance volume (V1) of the upper discharge port (V2> V1). .
[0008]
According to a third aspect of the present invention, in the hermetic compressor according to the first or second aspect, the refrigerant is an HFC refrigerant or a refrigerant mainly composed of an HFC refrigerant.
[0009]
According to a fourth aspect of the present invention, in the hermetic compressor according to the third aspect, when the top clearance volume (VA + Va) or the top clearance volume (V1 + V2) is expressed by the following empirical formula (1) or (2): , A top clearance volume (VA + Va) or top clearance volume (V1 + V2) is determined so that a is in the range of 3-7.
(VA + Va) = V ₀ / ρ _s × a (1)
Or (V1 + A2) = V ₀ / ρ _s × a (2)
Here, V ₀ represents the excluded volume, ρ _s represents the suction refrigerant density, and a is a coefficient.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view showing an example of a hermetic rotary compressor according to the present invention.
2A is an explanatory view for explaining the relationship among the cylinder 17A, the eccentric portion 18, the roller 19, the vane 20, the discharge port 23A, etc. of the hermetic rotary compressor of the present invention shown in FIG. 2 (b) is an explanatory view for explaining the relationship among the cylinder 17A, the roller 19, the upper bearing portion 21, the discharge port 23A, etc. of the hermetic rotary compressor of the present invention shown in FIG.
1 and 2, reference numeral 1 denotes an airtight container having an oil reservoir 2 in which oil is stored at the bottom. In the container, an electric element 3 is driven on the upper side and a rotating shaft 4 of the electric element is driven on the lower side. The rotary compression element 5 is accommodated. The electric element 3 includes a stator 6 fixed to the inner wall of the hermetic container 1 and a rotor 8 inserted into the rotating shaft 4 via an air gap 7 inside the stator. The stator 6 includes an iron core 10 having an oil return hole 9 by a notch on the outer periphery and a winding 12 having a coil end 11 facing up and down. Reference numeral 13 denotes an iron core of the rotor 8.
[0011]
The rotary compression element 5 includes two cylinders 17A and 17B. Since the cylinders 17A and 17B have substantially the same configuration, the configuration of the cylinder 17A will be described for simplicity. A roller 19 that rotates in the cylinder 17A by the eccentric portion 18 of the rotating shaft 4, a vane 20 that contacts the roller and divides the cylinder 17A, an upper bearing portion 21 that seals the opening of the cylinder 17, and the upper bearing portion 21 A discharge port 23A provided with the provided discharge valve 23 and a cup muffler 24A covering the discharge valve 23 are configured. A discharge port 25 is provided on the upper surface of the cup muffler.
[0012]
26 is a refrigerant discharge pipe, and this refrigerant discharge pipe is provided through an end cap 27 that seals the upper part of the hermetic container 1. Reference numeral 28 denotes an accumulator. Arrows indicate the refrigerant flow.
[0013]
In the hermetic rotary compressor configured as described above, the refrigerant flowing into the cylinder 17A from the suction port 30A through the accumulator 28 is compressed by the cooperation of the roller 19 and the vane 20, and the discharge valve 23A is discharged from the discharge port 23A. It is opened and discharged into the cup muffler 24A. The refrigerant in the cup muffler is discharged from the discharge port 25 through the air gap 7 of the electric element 3 to the upper part of the electric element. The refrigerant discharged to the upper part of the electric element 3 is swung by the rotation of the rotor 8, and the heavy oil contained therein is spun off to the inner wall side of the sealed container 1 by centrifugal force due to the swirling and separated. Yes. The refrigerant from which the oil is separated is discharged out of the sealed container 1 from the discharge pipe 26. The separated oil is returned to the oil reservoir 2 from the oil return hole 9 of the stator 6.
[0014]
On the other hand, the refrigerant flowing into the cylinder 17B from the suction port 30B through the accumulator 28 is similarly compressed by the cooperation of the roller and the vane, and the discharge valve (not shown) is opened from the discharge port 23B (not shown) to open the inside of the cup muffler 24B. Discharged. The refrigerant in the cup muffler 24B is introduced into the lower part of the electric element 3 through the passage 31 in the sealed container and the passage 32 outside the sealed container, and is discharged to the upper part of the electric element through the air gap 7 and the like.
[0015]
2 corresponds to the top clearance volume (V1) of the discharge port 23A which is the upper discharge port in the present invention (including the volume of the notch 33 of the cylinder 17A). On the other hand, although not illustrated, the top clearance volume (V2) of the lower discharge port referred to in the present invention is the top clearance volume of the discharge port 23B (not shown) (including the volume of the notch portion of the cylinder 17B).
The flow path resistance of the refrigerant discharged from the discharge port 23B, which is a lower discharge port (not shown), into the cup muffler 24B and introduced into the lower portion of the electric element 3 through the passage 31 inside the sealed container and the passage 32 outside the sealed container is: It is larger than the flow path resistance of the refrigerant that is discharged into the cup muffler 24A from the discharge port 23A that is the upper discharge port and discharged from the discharge port 25 of the cup muffler to the lower portion of the electric element 3.
Therefore, in the present invention, the top clearance volume (V2) of the lower discharge port is made larger than the top clearance volume (V1) of the upper discharge port (V2> V1) to compensate for the influence of the difference in the flow path resistance of the refrigerant. It is what.
[0016]
In the above example, the case where there are two cylinders has been described. However, the number of cylinders may be two or more, and if each top clearance volume is determined in the same manner as described above so as to compensate for the influence due to the difference in each flow path resistance of the refrigerant. Even in this case, the effects of the present invention are exhibited.
In the present invention, even if there is a single cylinder and a plurality of discharge ports, if each top clearance volume is determined so as to compensate for the influence of the difference in the flow path resistance of the refrigerant corresponding to each discharge port, There is an effect.
[0017]
In the present invention, it is preferable to determine each top clearance volume so that the sum (VA + Va) or (VA + Va) of the top clearance volumes satisfies the empirical formula (1) or (2).
[0018]
FIG. O. It is a graph which shows the relationship between P and the coefficient a. Conventionally, the coefficient a is about 8.5. O. P was about 4.0. From FIG. 3, the coefficient a is set to 3 to 7, preferably 4 to 6, so that C.I. O. It can be seen that P can be improved from 4.0 to 4.1.
When a high density, for example, R410A is used as the HFC-based refrigerant, for example, C. is more effectively achieved by setting the coefficient a within the above range. O. P can be improved.
[0019]
【The invention's effect】
By configuring the present invention as described above, the C.I. O. An improvement in P can be achieved.
The hermetic compressor according to the present invention is economical because it has a simple structure, and is highly effective as described above and has high industrial utility value.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of a hermetic compressor of the present invention.
2A is an explanatory diagram for explaining a relationship among a cylinder, an eccentric portion, a roller, a vane, a discharge port, and the like of the hermetic compressor of the present invention shown in FIG. 1, and FIG. It is explanatory drawing explaining the relationship of a cylinder, a roller, an upper bearing part, a discharge port, etc. of the sealed rotary compressor of this invention shown in FIG.
FIG. O. It is a graph which shows the relationship between P and the coefficient a.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Airtight container 2 Oil reservoir 3 Electric element 4 Rotating shaft 5 Rotation compression element 6 Stator 7 Air gap 8 Rotor 9 Oil return hole 17A, 17B Cylinder 18 Eccentric part 19 Roller 20 Vane 21 Upper bearing part 22 Lower bearing part 23 Discharge Valve 23A Discharge port 24A, 24B Cup muffler 25 Discharge port 26 Refrigerant discharge pipe 27 End cap 30A, 30B Suction port 31, 32 Passage 33 Notch

Claims (4)

An electric element having a rotating shaft on the upper side and a compressing element driven by the rotating shaft of the electric element on the lower side are housed, and the sucked refrigerant is compressed by this compressing element and discharged into a sealed container, and then sealed. A hermetic compressor that discharges to the outside of the container, and the compression element includes a cylinder having a suction port, a roller that rotates in the cylinder by an eccentric portion of the rotating shaft, and a roller that is in contact with the roller. A vane that separates the inside of the cylinder, an upper bearing portion and a lower bearing portion that seal the opening of the cylinder, a plurality of discharge ports provided with discharge valves provided in these bearing portions, and a cup muffler that covers these discharge valves In the configured hermetic compressor, the top clearance volume (VA) of the discharge port having the larger flow path resistance of the refrigerant discharged from the discharge port into the sealed container is set as the flow path of the refrigerant. Anti is greater than towards the top clearance volume of the discharge port (Va) small (VA> Va) hermetic compressor, characterized in that. After storing an electric element having a rotating shaft on the upper side and a plurality of compression elements driven by the rotating shaft of the electric element on the lower side, the sucked refrigerant is compressed by the compressing element and discharged into the sealed container A hermetic compressor that discharges to the outside of the hermetic container, and each of the plurality of compression elements includes a cylinder having a suction port, and a roller that rotates in the cylinder by the eccentric portion of the rotating shaft. And an upper bearing portion that seals the opening of the upper cylinder, a lower bearing portion that seals the opening of the lower cylinder, and a discharge valve provided on the upper bearing portion. In a hermetic compressor including a discharge port, a cup muffler covering the discharge valve, a lower discharge port provided with a discharge valve provided in a lower bearing portion, and a cup muffler covering the discharge valve The lower top clearance volume of the discharge port (V2) was higher than the top clearance volume (V1) of the upper discharge port (V2> V1) hermetic compressor, characterized in that. The hermetic compressor according to claim 1 or 2, wherein the refrigerant is an HFC refrigerant or a refrigerant mainly composed of an HFC refrigerant. When the top clearance volume (VA + Va) or the top clearance volume (V1 + V2) is expressed by the following empirical formula (1) or (2), the top clearance volume (VA + Va) or the top clearance so that a is in the range of 3 to 7. 4. The hermetic compressor according to claim 3, wherein the volume (V1 + V2) is determined.
(VA + Va) = V ₀ / ρ _s × a (1)
Or (V1 + A2) = V ₀ / ρ _s × a (2)
Here, V ₀ represents the excluded volume, ρ _s represents the suction refrigerant density, and a is a coefficient.

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