JP2003097458A - Sealed compressor and method of manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of becoming difficult for providing a highly efficient and excellently reliable compressor since a shaft inclines in a clearance range of a journal bearing and is in a state of end tooth bearing at both ends of the journal bearing, and an oil film is easily cut. SOLUTION: An annular slit groove and an outer diameter thin part are constituted in an end part of a journal bearing part, and rigidities of both ends of the journal bearing is reduced, and when the shaft is in a state of end tooth bearing, since the bearing is deformed along the shaft, the end tooth bearing is relieved.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor used for refrigerating and air conditioning equipment and the like for compressing a refrigerant.

2. Description of the Related Art A hermetic compressor for compressing a refrigerant of a refrigerating and air-conditioning apparatus is classified into a reciprocating type, a rolling piston type, a scroll type and the like according to its compression mechanism. These compression mechanisms are driven by connecting them to a power source such as an electric motor via a main shaft, but a large radial stress is applied to the main shaft by the compression operation, and as a result, the main shaft and the journal bearing that supports the main shaft are supported. Is a severe sliding condition in which one-sided contact is likely to occur. A conventional technique will be described below with reference to the drawings by taking a scroll type hermetic compressor as an example. FIG. 3 shows a vertical sectional view of a conventional scroll compressor. In FIG. 3, reference numeral 1 denotes a closed container, a housing 41 integrally formed with the compression mechanism 2, the electric motor 7, the main shaft 5, and the journal bearing 8, and a muffler 2.
1 and the like are housed inside, and a suction pipe 11 for sucking the refrigerant gas from the outside and a discharge pipe 16 for discharging the compressed refrigerant gas to the outside of the closed container are provided. Further, the bottom of the closed container 1 is an oil sump 10 that stores the lubricating oil 9. Compression mechanism 2
Is a fixed scroll 2a having a discharge port at its center, a movable scroll 2b having an eccentric bearing 2c formed on the end face on the side opposite to the scroll wrap, an Oldham ring 20 for restraining the rotation of the movable scroll 2b, and a discharged refrigerant gas. It is composed of a check valve 19 for preventing backflow. Housing 4
Reference numeral 1 supports a main shaft 5 by a journal bearing 8 which is sandwiched between a movable scroll 2b and a fixed scroll 2a so as to be slidable in a direction perpendicular to the axis, and an inner peripheral surface of which is finished to integrally form a journal bearing 8. . The main shaft 5 has a through hole 13 penetrating in the axial direction, one end is immersed in the oil sump 10, and the other end forms an eccentric shaft 5a.
The eccentric shaft 5a is an eccentric bearing 2c formed on the movable scroll.
Is rotatably inserted in. The electric motor 7 is composed of a stator 7b that is shrink-fitted and fixed to the inner wall of the closed container 1, and a rotor 7a that is fixed to the main shaft 5. Next, the operation of the compressor having the above structure will be described. The low-pressure gas returned from the refrigeration cycle is sucked into the compression mechanism 2 via the suction pipe 11. The compression mechanism 2 rotates the movable scroll 2b relative to the fixed scroll 2a so as not to rotate, and moves a plurality of compression spaces formed between the fixed scroll 2a and the movable scroll 2b from the outside to the inside. The compression operation is performed by gradually reducing the size. The compressed gas becomes a high-pressure gas, is once discharged to the muffler 21, then passes through the closed container 1 and is discharged from the discharge pipe 16 to the outside of the closed container 1 to be supplied to the refrigeration cycle. On the other hand, the lubricating oil 9 is pumped up by the pressure difference in the pump or the hermetically sealed container and rises in the through hole 13 of the main shaft 5 to lubricate and cool the journal bearing 8, the eccentric bearing 2c and each sliding portion,
A lubricating cycle is formed in which the pressure adjusting valve provided in the fixed scroll 2a sucks into the compression chamber, compresses it together with the refrigerant gas, separates the lubricating oil and the refrigerant gas in the closed container, and returns to the oil sump 10. In addition, the spindle 5 and the housing 4
A gray cast iron material is used for 1, and a compound layer mainly containing iron nitride is formed on the sliding portion. A radial load acts on the orbiting scroll due to the radial component of the gas pressure in the compression chamber and the inertial force. This load rotates in the same direction as the rotation of the main shaft 5 and is supported by the journal bearing 8 via the eccentric bearing 2c. That is, the spindle 5 is
A very large load generated by gas compression or the like causes the journal bearing 8 to rotate while being pressed against the inner surface of the journal bearing 8.
Further, in the processing of the bearing, it is general that most of the shape is processed and finally the journal bearing is finished.

However, in the above-mentioned conventional structure, since the eccentric bearing 2c receives a force, the main shaft 5 tilts in the range of the clearance of the journal bearing 8 and the journals on the eccentric shaft 5a side and the rotor 7a side. Since the bearing 8 is in a one-side contact state and the oil film is easily cut off, the driving force may increase and efficiency may be reduced, or the shaft and the bearing may be worn to impair reliability. The present invention solves such a conventional problem, and an object thereof is to alleviate one-side contact of a shaft and to improve efficiency and reliability.

In order to solve the above-mentioned problems, the present invention provides means for lowering the rigidity as compared with the central portion at both axial end portions of a housing holding a journal bearing. Further, according to the present invention, the processing for providing the means for lowering the rigidity is performed before finishing the inner peripheral surface of the journal bearing to prevent the inner periphery of the journal bearing from becoming a drum shape.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a vertical sectional view of a scroll compressor according to a first embodiment of the present invention. Here, the structure of the compressor shown in FIG. 1 is the same as that of the conventional scroll compressor detailed in FIG. 3, and the same numbers are used for the same functional parts. Further, description of the same configuration and operation as the conventional example will be omitted. An annular slit groove 4a is formed on the compression mechanism side of the housing 4 formed integrally with the journal bearing 8 and an outer peripheral thin portion 4b is formed on the rotor 7a side. In this configuration, the load acting on the movable scroll 2b when compressed is from the eccentric bearing 6 to the eccentric shaft 5a.
And is held by the journal bearing 8 from the main shaft 5. Considering the compression mechanism 2 side from the journal bearing 8, since it is cantilevered, the main shaft 5 is deformed and the main shaft 5 is deformed.
Therefore, an inclination corresponding to the clearance between the journal bearing 8 is generated, and an excessive load is applied to the compression mechanism 2 side of the journal bearing 8 by the main shaft 5. However, since the annular slit groove 4a is formed on the outer circumference, the rigidity of the journal bearing 8 on the side of the compression mechanism 2 becomes low and the journal shaft 8 conforms to the inclination of the main shaft 5, so that one-sided contact can be alleviated. Further, a thin portion 4b is formed on the outer circumference on the opposite side of the journal bearing 8, and the inclination is allowed by the annular slit groove 4a.
Where the one-side contact on the side of the rotor 7a also becomes severe, the thin portion 4b on the outer periphery has low rigidity, so that the one-side contact can be similarly mitigated. (Embodiment 2) FIG. 2 shows a process of manufacturing a bearing component of a scroll compressor according to an embodiment of the present invention. Housing 4
The inner diameter of the bearing is machined to form the journal bearing 8, but after the inner diameter is finished, the annular slit groove 4a and the thin portion 4b are processed.
Is being processed. By processing in such a process, the rigidity is uniform because there is no annular slit groove 4a or thin portion 4b when the journal bearing 8 is finished, so that the diameter of both ends generated by the spring back after processing is reduced. The shape of the mold can be prevented. When the drum type is used, the one-sided contact generated due to the inclination of the shaft in the journal bearing becomes strict, but the one-sided contact does not become strict because the drum-shaped type does not cause the drum-shaped contact. Furthermore, since there is an annular slit groove and a thin outer peripheral portion, it is possible to obtain a high effect of mitigating one-side contact.

As is apparent from the above embodiment, according to the invention of claim 1, the rigidity of both ends of the main bearing is lowered by the annular slit groove and the thin portion on the outer periphery, and both ends of the journal bearing due to the inclination of the shaft. Since it is possible to reduce the uneven contact, it is possible to provide a highly efficient and highly reliable compressor. Further, according to the invention of claim 5, the rigidity of both ends of the journal bearing is reduced by the annular slit groove and the thin portion of the outer circumference without forming the drum-shaped inner diameter. Since the hit is alleviated more effectively, a more efficient and reliable compressor can be provided.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a scroll compressor showing an embodiment of the present invention.

FIG. 2 is a process drawing of a bearing component showing another embodiment of the present invention.

FIG. 3 is a vertical sectional view of a conventional scroll compressor.

[Explanation of symbols]

1 closed container 2 compression mechanism 4 housing 4a annular slit groove 4b Thin part 5 spindle 7 electric motor 8 journal bearings

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hidenobu Shintaku             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Kei Morimoto             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Noboru Iida             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 3H003 AA05 AB03 AC03 AD01 CA00                 3H029 AA02 AA14 AB03 BB01 BB16                       BB33 BB43 BB44 CC17 CC18                 3H039 AA03 AA06 AA12 BB03 BB04                       BB05 BB07 BB11 BB15 BB28                       CC09                 3J011 AA01 BA02 DA02 EA10 KA02                       MA12

Claims (5)

[Claims] 1. A compression mechanism that compresses and discharges sucked gas, an electric motor that includes a rotor and a stator that drives the compression mechanism, a main shaft that connects the compression mechanism and the electric motor, and the compression mechanism. A journal bearing that is arranged between the mechanism and the electric motor to support the main shaft, and a housing integrally formed with the journal bearing are housed in a hermetically sealed container, and the compression mechanism, the electric motor stator, and the housing are hermetically sealed. A hermetic compressor fixed to an inner wall surface of a container, characterized in that means for lowering rigidity as compared with a central portion is provided at both axial ends of the housing. 2. The hermetic compressor according to claim 1, wherein
A hermetic compressor characterized in that an annular slit is provided at an end of the housing as a means for reducing rigidity. 3. The hermetic compressor according to claim 1, wherein
A hermetic compressor characterized in that the outer peripheral wall thickness of the housing end portion is made thinner than that of the central portion as means for reducing rigidity. 4. The hermetic compressor according to claim 1, wherein
A hermetic compressor, characterized in that, as means for reducing rigidity, an annular slit is formed at the end of the housing on the side of the compression mechanism, and the outer peripheral wall thickness of the end of the housing on the electric motor side is made thinner than that in the central part. 5. The method for manufacturing the hermetic compressor according to claim 1, further comprising the step of finishing the inner diameter of the journal bearing and then providing a means for reducing rigidity at the end of the housing. A method for manufacturing a hermetic compressor, characterized by applying the method.