JP3747528B2 - Compressor for refrigerator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a compressor for a refrigerator used in an air conditioner and a refrigerator.
[0002]
[Prior art]
A conventional compressor for a refrigerator is shown in FIG. A compression mechanism 102 and an electric motor 104 that drives the compression mechanism 102 via a drive shaft 103 are horizontally arranged inside the sealed container 101, and the drive shaft 103 is disposed on the main bearing 105 on the compression mechanism 101 side and on the electric motor 104 side. It is supported by the auxiliary bearing 106. The auxiliary bearing 106 is a rolling bearing and is accommodated in an auxiliary bearing chamber 108 provided in an auxiliary bearing holding member 107 fixed to the sealed container 101. The back of the auxiliary bearing chamber 108 is an oil pump 109, and the auxiliary bearing 106 is lubricated with lubricating oil leaking from the oil pump 109.
[0003]
The conventional example shown in FIG. 4 is a compressor described in Japanese Patent Laid-Open No. 1-170779, and the auxiliary bearing 106 is a rolling bearing that is inserted and fixed to an auxiliary bearing holding member 110 that holds the auxiliary bearing 106.
[0004]
On the other hand, specific Freon R12 and R22 were used as the refrigerant. However, in recent years, it has been confirmed that specific chlorofluorocarbons contain chlorine atoms in the molecule, which causes destruction of the ozone layer, and alternative chlorofluorocarbons are being developed and used. As an alternative refrigerant having high practicality, a refrigerant such as HFC not containing chlorine is cited. In addition, the refrigeration oil must be compatible with the refrigerant from the viewpoint of lubrication that is carried and supplied to each part of the compressor by the flow of the refrigerant, and from the viewpoint of heat exchanger efficiency. Mineral oil and alkylbenzene have been used for specific chlorofluorocarbons, and since this is extremely poorly compatible with the above-mentioned alternative chlorofluorocarbon, it is considered to use ester oil compatible with the alternative refrigerant.
[0005]
[Problems to be solved by the invention]
However, in the above conventional configuration, since the alternative refrigerant does not contain chlorine, lubricity like conventional specific chlorofluorocarbon cannot be expected. For this reason, sliding conditions become severe and high wear resistance is required. In the conventional example of FIG. 3, a rolling bearing 106 is disposed in a sub-bearing chamber 108 which is a closed space, and the rolling elements and races of the rolling bearing rise in temperature due to frictional heat in the drive shaft 103 and the rolling bearing 106. And shorten the bearing life. Further, in the conventional example of FIG. 4, since the refrigerant gas passes through the rolling bearing, it is possible to prevent the rolling bearings and races of the rolling bearing from rising in temperature due to frictional heat, but the amount of lubricating oil that can be supplied is small. Oil shortage shortens bearing life. In the case of a hermetic compressor that is maintenance-free and operates with a long service life, the bearing life becomes the life of the entire compressor, which is a particular problem and cannot be put into practical use.
[0006]
The present invention solves such a conventional problem, and provides a compressor for a refrigerator that does not have a problem of life reduction due to a bearing even when an alternative refrigerant not containing chlorine and a compatible ester oil are used in combination. It is intended to provide.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a compression mechanism and a motor that drives the compression mechanism via a drive shaft in a sealed container, and the drive shaft is connected to the main bearing on the compression mechanism side and the motor side. The secondary bearing is used as a rolling bearing and is housed in a secondary bearing chamber provided in a secondary bearing holding member fixed to the sealed container or the electric motor, and the secondary bearing is sandwiched between the secondary bearing chambers. By providing a refrigerant population and an outlet, the lubricating oil is stored in the auxiliary bearing chamber, the supply of lubricating oil to the auxiliary bearing is increased, and the inlet / outlet for flowing the refrigerant to the auxiliary bearing is provided. It is possible to prevent the rolling elements and races of rolling bearings from rising due to heat, and a highly reliable compressor with a long bearing life even when fluorocarbon hydrogen refrigerant is used as refrigerant and ester oil is used as refrigeration oil. Can be supplied.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In the compressor for a refrigerator according to claim 1 of the present invention, a compression mechanism and an electric motor for driving the compression mechanism via a drive shaft are horizontally arranged inside the sealed container, and the drive shaft is connected to a main bearing on the compression mechanism side. The secondary bearing is supported by a secondary bearing on the motor side, and the secondary bearing serves as a rolling bearing. The secondary bearing is housed in a secondary bearing chamber provided in the secondary container holding member fixed to the hermetic container or the electric motor, and the secondary bearing chamber includes the secondary bearing. A refrigerant population and an outlet are provided , and an outlet of the refrigerant is provided above the auxiliary bearing chamber. The supply of lubricating oil to the auxiliary bearing is abundant, and an inlet / outlet for supplying the refrigerant to the auxiliary bearing is provided. As a result, the temperature of rolling elements and races of the rolling bearing due to frictional heat can be prevented, and the amount of lubricating oil supplied to the secondary bearing can be increased. Therefore, a highly reliable compressor with a long bearing life Can be supplied.
[0009]
In the invention according to claim 2, since the oil reservoir is provided in the auxiliary bearing chamber, the supply of lubricating oil to the auxiliary bearing can be increased, and a highly reliable compressor with a long bearing life can be supplied. .
[0011]
According to the third aspect of the present invention, the wall constituting the auxiliary bearing chamber is constituted by an oil pump case, and the structure of supplying lubricating oil is simplified and can be constructed at low cost.
[0012]
The invention of claim 4 is provided with a shielding plate in the vicinity of the refrigerant outlet of the auxiliary bearing chamber, and the lubricating oil that lubricates the rolling bearing in the auxiliary bearing chamber is captured by the shielding plate that comes out together with the refrigerant. Reduces the lubricating oil taken from the compressor to the refrigeration cycle, prevents a decrease in the lubricating oil in the compressor, can provide a highly reliable compressor, and increases the efficiency of the refrigeration cycle because less lubricant is discharged. it can.
[0013]
The invention of claim 5 provides an oil supply path from the oil pump to the sub-bearing chamber in the invention of claim 1 , and the amount of lubricating oil popped into the refrigeration cycle even if the amount of lubricating oil supplied to the sub-bearing is increased. Therefore, a highly reliable compressor can be provided.
[0014]
The invention of claim 6 applies the above-described configuration to a refrigerant in which at least one or two or more of a fluorocarbon hydrogen refrigerant group is mixed as a refrigerant and ester oil that is compatible with the refrigerant is used as a refrigerating machine oil. By doing so, it is possible to improve the durability of the rolling bearing, which tends to be insufficient, and to provide a highly reliable compressor.
[0015]
【Example】
Hereinafter, a compressor for a refrigerator as an embodiment of the present invention will be described with reference to the drawings.
[0016]
The compressor for a refrigerator of this embodiment is a hermetic compressor, and as shown in FIG. 1 as a whole, the refrigerant is sucked into one end side of the hermetic container 1 constituting the horizontal type pressure container. A compression mechanism 2 for compression is provided. The stator 4 of the electric motor 3 that drives the compression mechanism 2 is positioned at the center of the hermetic container 1 and is fixed to the inner surface of the side peripheral wall of the hermetic container 1, and the rotor 5 corresponding to the stator 4 of the electric motor 3 includes A crankshaft 6 that is a drive shaft of the compression mechanism 2 is coupled, and the drive shaft is arranged to be substantially horizontal. The crankshaft 6 is supported by a slide bearing 9 fixed to a main bearing member 10 fixed by screwing a main shaft 8 at one end of the compression mechanism 2 to the compression mechanism 2, and is opposite to the main shaft 8. The other end is supported by a sub-bearing 12 disposed on a sub-bearing holding member 11 fixed to the inner surface of the side wall of the hermetic container 1. The auxiliary bearing holding member 11 divides a space into a motor chamber 13 and a discharge chamber 14 on the motor side on the side opposite to the compression mechanism 2 between the sealed container 1 and the motor 3. A discharge pipe 15 is attached to the sealed container 1 of the discharge chamber 14. The auxiliary bearing holding member 11 may be fixed to the stator 4 of the electric motor 3 instead of the sealed container 1. The auxiliary bearing 12 is a radial type rolling bearing. The rolling element 12a of the rolling bearing 12 is a ball, but a roller or other object may be adopted as necessary.
[0017]
FIG. 2 shows a partial view of the auxiliary bearing 12 that supports the other end of the crankshaft 6. The auxiliary bearing holding member 11 is formed in a concave shape in the direction of the electric motor 3, and the auxiliary bearing 12 that is a rolling bearing is inserted into the concave portion 16. The crankshaft 6 is inserted into the inner ring 12 b of the rolling bearing 12. An oil pump 17 is attached to the tip of the crankshaft, and this oil pump 17 is housed in a pump case 18. The back portion 18 a of the pump case 18 is screwed 19 to the flat portion 11 a of the auxiliary bearing holding member 11. A sub bearing chamber 20 is constituted by the pump case back portion 18 a and the concave portion 16 of the sub bearing holding member 11. An inlet hole 21 is formed at the end of the recess 16 of the auxiliary bearing holding member 11, and the crankshaft 6 is inserted therein. A notch is provided above the pump case back portion 18 a to form an outlet hole 22. A shielding plate 23 is provided so as to cover the opening of the outlet hole, and this shielding plate 22 also covers the communication hole 24 opened in the auxiliary bearing holding member 11.
[0018]
In the oil pump 17, a suction port 25 is opened in the lubricating oil reservoir 7, and a discharge port is connected to a lubricating oil hole 26 formed in the crankshaft 6 so as to extend vertically from an end portion to a portion of the sliding bearing 9. Thereby, the lubricating oil discharged by the oil pump 17 is supplied to each sliding portion of the compression mechanism 2 such as the sliding bearing 9 to lubricate them.
[0019]
The compression mechanism 2 in the present embodiment is a scroll type, and the compression mechanism 2 includes a fixed scroll 2a and a movable scroll 2b. The refrigerant gas from the suction pipe 27 of the compressor is received, and the refrigerant gas is compressed and discharged from the discharge port 28. At this time, the discharged refrigerant gas is mixed with lubricating oil that has lubricated the sliding portions, and is discharged together. The discharged refrigerant gas enters the sealed container 1 from the discharge port 28, cools the electric motor 3, and reaches the electric motor chamber 13 between the auxiliary bearing holding member 11 and the electric motor 3.
[0020]
The auxiliary bearing holding member 11 serves as a partition, and a part of the refrigerant enters the discharge chamber 14 through a communication hole 24 opened in the auxiliary bearing holding member 11. The other part of the refrigerant enters from the inlet hole 21 of the recess 16 of the auxiliary bearing holding member 11, cools the rolling bearing 12, and is discharged from the outlet hole 22 of the pump case 18. The lubricating oil mixed in the refrigerant lubricates the rolling bearing 12. For this reason, it is possible to prevent the rolling elements and the race from rising due to the frictional heat of the rolling bearing 12 and to supply a highly reliable compressor with a long bearing life.
[0021]
The shaft end portion 6a of the crankshaft 6 that drives the oil pump 17 is inserted from the auxiliary bearing chamber 20 through the hole 18b of the pump case 18, and the gap between the shaft end portion 6a and the hole 18b becomes a passage 29a for the lubricating oil. Lubricating oil is supplied from the pump 17 to the auxiliary bearing chamber 20. This lubricating oil accumulates in the lower part of the sub bearing chamber 20 and lubricates the 30 rolling bearing. Lubricating oil mixed with the refrigerant is also separated and stored in the lubricating oil reservoir 30 of the auxiliary bearing chamber 20 in the auxiliary bearing chamber. When the amount of lubricating oil to the auxiliary bearing 12 is further increased, a small hole 29b connected to the lubricating oil hole 26 may be provided in the crankshaft 6, or an oil groove may be provided in the hole 18a of the crankcase. When the supply amount of the lubricating oil from the oil pump 17 to the sub-bearing chamber 20 is increased, the lubricating oil in the sub-bearing chamber 20 is stirred by the rolling bearing 12 and is blown off in droplets. As a result, a large amount of lubricating oil is mixed with the refrigerant flowing through the outlet hole, and when it enters the discharge chamber 14 as it is, the refrigerant is discharged from the discharge pipe 15 to the outside of the compressor while containing a large amount of lubricating oil. This results in a compressor with a large amount of reliability, and the reliability and performance deteriorate. In order to prevent this, a shielding plate 23 is provided in the vicinity of the outlet hole 22 so as to cover the outlet portion, and a refrigerant containing lubricating oil collides with the shielding plate 23 or curves to separate the lubricating oil. Since the separated lubricating oil falls into the lubricating oil reservoir 7, the amount of lubricating oil contained in the refrigerant is reduced, and a compressor with less oil discharge is realized.
[0022]
When a mixed refrigerant in which at least one or two or more of a fluorocarbon hydrogen refrigerant group such as HFC is mixed is used as the refrigerant, and an ester oil compatible with the refrigerant gas is used as the lubricating oil, the refrigerant is chlorine. Therefore, lubricity like conventional specific Freon cannot be expected. For this reason, the sliding conditions become severe, and in rolling bearings, sufficient lubrication cannot be obtained and the fatigue life tends to decrease. Therefore, it is very effective to apply the above-described configuration to the refrigerant compressor. Therefore, a highly reliable compressor with a long bearing life can be supplied. Further, the amount of oil stored in the auxiliary bearing chamber 20 increases, the amount of lubricating oil supplied to the auxiliary bearing 12 can be increased, and a highly reliable compressor with a long bearing life can be supplied. .
[0023]
【The invention's effect】
As is clear from the above embodiment, according to the first aspect of the invention, in the horizontal compressor, the rolling bearing is housed in the auxiliary bearing chamber, the refrigerant inlet and outlet are provided in the auxiliary bearing chamber, and the outlet is further provided . Is provided above the auxiliary bearing chamber , so that the supply of lubricating oil to the auxiliary bearing can be increased, the temperature of the rolling bearing can be prevented from rising, and the amount of lubricating oil supplied to the auxiliary bearing can be increased. A highly reliable compressor with a long lifetime can be supplied.
[0024]
According to the second aspect of the present invention, since the oil reservoir is provided in the auxiliary bearing chamber, the supply of lubricating oil to the auxiliary bearing can be more abundant, and a highly reliable compressor with a long bearing life can be provided. Can be supplied .
[0025]
The invention of claim 4 is provided with a shielding plate in the vicinity of the refrigerant outlet of the auxiliary bearing chamber, and the lubricating oil that lubricates the rolling bearing in the auxiliary bearing chamber is captured by the shielding plate that comes out together with the refrigerant. Reduces the lubricating oil taken from the compressor to the refrigeration cycle, prevents a decrease in the lubricating oil in the compressor, can provide a highly reliable compressor, and increases the efficiency of the refrigeration cycle because less lubricant is discharged. it can. The invention of claim 5 provides an oil supply path from the oil pump to the sub-bearing chamber, and even if the amount of lubricating oil supplied to the sub-bearing is increased, the amount of lubricating oil jumping into the refrigeration cycle does not increase. A highly reliable compressor can be provided.
[0026]
The invention of claim 6 applies the above configuration to a refrigerant in which at least one or a mixture of two or more of a fluorocarbon hydrogen refrigerant group is used as a refrigerant and ester oil that is compatible with the refrigerant is used as a refrigerating machine oil. By doing so, the durability of the rolling bearing, which tends to be insufficient, can be improved, and a highly reliable compressor can be supplied.
[Brief description of the drawings]
FIG. 1 is a transverse sectional view showing a compressor for a refrigerator as one embodiment of the present invention. FIG. 2 is an enlarged sectional view in the vicinity of a sub-bearing chamber showing an embodiment of the present invention. Cross section of compressor [Fig. 4] Cross section of other conventional compressors for refrigerators [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Airtight container 2 Compression mechanism 3 Electric motor 6 Drive shaft 10 Main bearing member 11 Sub bearing holding member 12 Sub bearing (rolling bearing)
17 Oil pump 18 Oil pump case 21 Inlet hole 22 Outlet hole 23 Shield plate 29b Oil supply path (small hole)

Claims (6)

A compression mechanism and an electric motor that drives the compression mechanism via a drive shaft are horizontally disposed inside the sealed container, and the drive shaft is supported by a main bearing on the compression mechanism side and a sub bearing on the motor side. It is a rolling bearing and is housed in a sub-bearing chamber provided in a sub-bearing holding member fixed to the hermetic container or the motor, and a sub-bearing is sandwiched in the sub-bearing chamber to provide a refrigerant population and an outlet , The compressor for refrigerators which provided the exit of the refrigerant | coolant above the said auxiliary bearing chamber .   The compressor for a refrigerator according to claim 1, wherein the auxiliary bearing chamber has an oil reservoir. The compressor for a refrigerator according to any one of claims 1 and 2, wherein a wall constituting the auxiliary bearing chamber is an oil pump case. The compressor for a refrigerator according to claim 1 , wherein a shielding plate is provided in the vicinity of an outlet opening provided in the auxiliary bearing chamber . A compressor for a refrigerator according to claim 1, wherein the oil pump is provided an oil supply path to the sub-bearing chamber. 6. The refrigerator for a refrigerator according to any one of claims 1 to 5 , wherein a mixed refrigerant obtained by mixing at least one or two or more of a fluorocarbon hydrogen refrigerant group is used as the refrigerant, and ester oil compatible with the refrigerant is used as the refrigerator oil. Compressor.

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