JP2010255421A - Rotary compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problems: since an HFC-based refrigerant as the substitute refrigerant of an HCFC-based refrigerant conventionally used in a compressor causes the inside of the compressor to become high in pressure during operation in comparison with the HCFC-based refrigerant and is inferior in oil lubricity, abnormal wear and seizure occur in a compression mechanism part, in particular, the inner peripheries of a main bearing and a sub bearing, and in order to solve this problem, such a method is employed that bearing ring-shaped grooves are formed in the end surfaces of the main baring and sub bearing on the side of a compression chamber to reduce a baring load; meanwhile, a sliding area of a piston with a shaft is reduced to increase bearing pressure, and abnormal wear occurs at the end surfaces of the main bearing and sub bearing on the side of the compression chamber. <P>SOLUTION: In this rotary compressor, the grooves 17 or holes distributed at less than 360° in a circumferential direction with respect to a bearing center are formed in the vicinity of an angle position with the bearing loads of the end surfaces of the main bearing and sub bearing on the side of the compression chamber maximized, and the bearing load is reduced while ensuring reliability of the end surfaces on the side of the compression chamber. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rotary compressor used in an air conditioner or the like, and more particularly to a rotary compressor that improves the reliability of a compression mechanism.

  Generally, a rotary compressor is known as a compressor used for an air conditioner, a refrigerator, or the like. The rotary compressor stores oil in a sealed container and an electric motor part, a compression mechanism part connected to the electric motor part, and a bottom part, and the compression mechanism part partitions a plurality of cylindrical cylinders and the plurality of cylinders. A partition plate, a main bearing and a sub-bearing constituting a compression chamber on both end faces of the plurality of cylindrical cylinders, a piston revolving in the compression chamber, a shaft coupled to the motor for revolving the piston, and the shaft A ring-shaped groove is formed on the end surfaces of the main bearing and the sub-bearing on the compression chamber side for the purpose of reducing bearing load. (See Patent Document 1).

Japanese Utility Model Publication No. 01-036692

  HCFC-based refrigerants that have been used for compressors in the past are said to contain chlorine and destroy the ozone layer, and the use of the HCFC-based refrigerants has been moving forward because it has an adverse effect on the global environment. As an alternative refrigerant, an HFC refrigerant not containing chlorine, for example, R-32, R-134a, and the like can be given. However, the HFC refrigerant has a higher pressure inside the compressor during operation than the HCFC refrigerant, and is inferior in oil lubricity. Therefore, problems such as abnormal wear and seizure occur in the inner periphery of the compression mechanism, especially the main bearing and sub-bearing. It was connected to. In order to solve the problem, a method of reducing the bearing load by forming a ring-shaped groove on the end surfaces of the main bearing and the sub-bearing on the compression chamber side as disclosed in Patent Document 1. However, on the other hand, since the sliding area with the piston and the shaft becomes small, the surface pressure increases, and problems such as abnormal wear of the end surfaces of the main bearing and the sub bearing on the compression chamber side are likely to occur.

  The present invention solves the above-mentioned problems, and provides a rotary compressor capable of improving the reliability of the compression mechanism by providing grooves or holes in the end surfaces of the main bearing and the sub-bearing on the compression chamber side. The purpose is to do.

  In order to achieve the above-mentioned object, the present invention stores an oil in an electric motor part and a compression mechanism part connected to the electric motor part and a bottom part in a sealed container. The compression mechanism part includes a plurality of cylindrical cylinders and a plurality of cylinders. An intermediate partition plate that partitions the cylinder, a main bearing and a sub bearing that constitute a compression chamber on both end faces of the plurality of cylindrical cylinders, a piston that revolves in the compression chamber, and the electric motor that imparts a revolving motion to the piston, In a rotary compressor having as components the combined shaft and vanes that further divide the cylindrical inner peripheral surfaces of the plurality of cylinders into a plurality of sealed spaces, the bearing load on the compression chamber side end surfaces of the main bearing and the sub-bearing is the largest. Grooves or holes distributed at less than 360 degrees in the circumferential direction with respect to the bearing center are provided in the vicinity of the increasing angular position.

According to the present invention, since the bearing load is reduced at the angular position where the bearing load is maximized and the sliding area with the piston and the shaft is large with respect to the groove of 360 degrees, a highly reliable rotary compressor can be obtained. .

Sectional view of a rotary compressor according to the present invention The figure which shows the main bearing in Embodiment 1 The figure which shows the main bearing in Embodiment 2. The figure which shows the main bearing in Embodiment 3.

  Embodiments of the present invention will be described below with reference to the drawings of FIGS. The rotary compressor in the embodiment of the present invention will be described by taking a two-stage rotary compressor as an example, but is not limited thereto, and can be applied to a one-stage rotary compressor or a multistage compressor having three or more stages. Needless to say.

(Embodiment 1)
FIG. 1 is a cross-sectional view of a rotary compressor according to the present invention. Reference numeral 1 in FIG. 1 denotes a sealed container, in which an electric motor part and a compression mechanism part and a shaft 9 for transmitting the rotational force of the electric motor to the compression mechanism part are housed. An oil 16 is stored in the closed container 1 at the bottom. The electric motor unit includes a stator 14 and a rotor 13. The compression mechanism includes two cylindrical cylinders 5 and 7, an intermediate partition plate 6 that partitions the cylinders 5 and 7, a main bearing 4 that constitutes a compression chamber on both end surfaces of the cylindrical cylinders 5 and 7, and a secondary bearing. 8, a piston 10 that revolves in the compression chamber, a shaft 9 that is coupled to the electric motor that revolves the piston 10, and an upper muffler chamber 2 that reduces noise caused by pulsation of gas discharged from the compressor section The lower muffler chamber 3 and the cylindrical inner peripheral surfaces of the plurality of cylinders 5 and 7 are further composed of a vane 11 that partitions the plurality of sealed spaces. In the case of this configuration, it is the main bearing, the intermediate partition plate, and the auxiliary bearing that slide with the piston end surface.

FIG. 2 shows the compression chamber side end face of the main bearing in the first embodiment. There is a groove 17 in a certain angle range of less than 360 degrees in the circumferential direction near the angular position where the bearing load becomes maximum during one rotation of the shaft, and the inner circumference of the bearing is deformed in the radial direction by this groove. By doing so, the bearing load can be reduced, and the reliability of the end face can be ensured because the sliding area with the piston and the shaft is large and the surface pressure is small as compared with the case of forming the groove of 360 degrees. Note that the present embodiment can also be applied to a secondary bearing.
(Embodiment 2)
FIG. 3 shows the compression chamber side end face of the main bearing in the second embodiment. Thus, by providing the circular hole 18 near the angular position where the bearing load is maximized, the reliability of the inner circumference of the bearing can be improved while ensuring the reliability of the end face on the compression chamber side. Note that the present embodiment can also be applied to a secondary bearing.
(Embodiment 3)
FIG. 4 shows the compression chamber side end face of the main bearing in the third embodiment. Thus, by providing the polygonal hole 19 near the angular position where the bearing load is maximized, the reliability of the inner circumference of the bearing can be improved while ensuring the reliability of the end face on the compression chamber side. Note that the present embodiment can also be applied to a secondary bearing.
(Embodiment 4)
The rotary compressor having this structure can be used for an HFC refrigerant not containing chlorine.
(Embodiment 5)
Furthermore, in recent years, compressors using natural refrigerants such as carbon dioxide, helium, and ammonia have been developed from the viewpoint of preventing global warming. The present invention can also be applied to a rotary compressor using such a natural refrigerant. In particular, since carbon dioxide has a higher pressure in the compression mechanism than HFC refrigerant, the present invention is more effective.
(Embodiment 6)
Furthermore, from the viewpoint of preventing global warming, it is possible to apply the present invention to a rotary compressor using a next-generation refrigerant HFO-1234yf having a low global warming coefficient or a mixed refrigerant thereof. (Embodiment 7)
Normally, various types of oil are used in the compressor depending on the refrigerant used and the material used for the compression mechanism. The present invention relates to natural products or oils derived from natural products such as naphthenic oil, paraffin oil and alkylbenzene oil, which are mainly used in compressors, and synthetic oils such as polyether oils and polyol ester oils, or the above natural oils. It is also possible to apply to mixed oils of oils derived from products or natural products and synthetic oils.
(Embodiment 8)
In order to improve mechanical properties, various additives may be added to the oil. The present invention comprises a copper deactivator such as benzotriazole, a sulfur-based extreme pressure additive, a halogen-based extreme pressure additive, a phosphorus-based extreme pressure additive, an organometallic compound-based extreme pressure additive, and combinations thereof. It can also be applied to a rotary compressor containing an effective amount of an extreme pressure additive or the like.

  As described above, according to the rotary compressor of the present invention, by ensuring the reliability of the compression chamber side end faces of the main bearing and the sub-bearing, the bearing load can be reduced at the angular position where the bearing load becomes maximum. Since a highly reliable rotary compressor can be obtained, it can be widely applied to heat pump applications such as dryers, dehumidifiers, and water heaters in addition to air conditioners and the like.

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Upper muffler chamber 3 Lower muffler chamber 4 Main bearing 5 Upper cylinder 6 Intermediate partition plate 7 Lower cylinder 8 Sub bearing 9 Shaft 10 Piston 11 Vane 12 Oil pickup 13 Rotor 14 Stator 16 Oil 17 Groove 18 of bearing end surface 18 Circular hole in bearing end face 19 Polygonal hole in bearing end face

Claims (9)

Oil is stored in the motor unit and a compression mechanism unit connected to the motor unit and a bottom part in the hermetic container, and the compression mechanism unit includes a plurality of cylindrical cylinders, an intermediate partition plate that partitions the cylinders, and the plurality of cylinders A main bearing and a sub-bearing that constitute a compression chamber on both end faces of the cylindrical cylinder, a piston that revolves in the compression chamber, a shaft that is coupled to the electric motor that revolves the piston, and a cylinder of the plurality of cylinders A rotary compressor having vanes that divide the inner peripheral surface into a plurality of sealed spaces as constituent elements, wherein the main bearing and the sub-bearing are grooves distributed at less than 360 degrees in the circumferential direction with respect to the bearing center on the end surface of the compression chamber A rotary compressor characterized by comprising: The rotary compressor is characterized in that the main bearing and the sub-bearing have holes of a certain depth on the end face on the compression chamber side. The rotary compressor according to claim 2, wherein the holes of the main bearing and the auxiliary bearing are circular. The rotary compressor according to claim 2, wherein the holes of the main bearing and the sub bearing are polygonal. The rotary compressor according to any one of claims 1 to 4, wherein HFC or the like not containing chlorine is used as a refrigerant. The rotary compressor according to any one of claims 1 to 4, wherein a natural refrigerant such as carbon dioxide, ammonia, or helium is used as the refrigerant. The rotary compressor according to any one of claims 1 to 4, wherein HFO-1234yf or a mixed refrigerant thereof is used as a refrigerant. Synthetic oils such as naphthenic oils, paraffinic oils, alkylbenzene oils and the like, and synthetic oils such as polyether oils and polyol ester oils, or oils derived from the natural products or natural products. The rotary compressor according to any one of claims 1 to 7, wherein a mixed oil of oil is used. The oil comprises a copper deactivator such as benzotriazole, a sulfur-based extreme pressure additive, a halogen-based extreme pressure additive, a phosphorus-based extreme pressure additive, an organometallic compound-based extreme pressure additive, and combinations thereof. The rotary compressor according to any one of claims 1 to 7, wherein an effective amount of other known additives such as an extreme pressure additive is blended.