阅读说明：本技术 压缩机 (Compressor with a compressor housing having a plurality of compressor blades ) 是由 横山哲英 岩崎俊明 堀口大辅 伊藤慎一 冈本政哉 小山修平 于 2018-03-05 设计创作，主要内容包括：本发明的压缩机具备：压缩机构部,其配置于密闭容器内；电动机部,其驱动压缩机构部；驱动轴,其将电动机部的驱动力向压缩机构部传递；主轴承,其支承驱动轴的上部；副轴承,其支承驱动轴的下部；径向承受面,其设置于副轴承,并将驱动轴的径向面支承为能够滑动；以及推力承受面,其将驱动轴的推力面支承为能够滑动。在推力面与推力承受面之间具有使推力面与推力承受面以曲面接触的接触点、和随着从接触点朝向径向外侧而连续地增加的缝隙。(The compressor of the present invention comprises: a compression mechanism unit disposed in the closed container; a motor unit that drives the compression mechanism unit; a drive shaft for transmitting the driving force of the motor to the compression mechanism; a main bearing supporting an upper portion of the drive shaft; a sub-bearing supporting a lower portion of the drive shaft; a radial bearing surface provided on the sub-bearing and supporting a radial surface of the drive shaft to be slidable; and a thrust receiving surface that slidably supports the thrust surface of the drive shaft. The thrust surface and the thrust receiving surface have a contact point between them, which makes the thrust surface and the thrust receiving surface contact with each other in a curved surface, and a gap which continuously increases from the contact point toward the radially outer side.)

1. A compressor, wherein,

the compressor is provided with:

a compression mechanism unit disposed in the closed container;

a motor unit that drives the compression mechanism unit;

a drive shaft that transmits a driving force of the motor unit to the compression mechanism unit;

a main bearing supporting an upper portion of the drive shaft;

a sub-bearing supporting a lower portion of the drive shaft;

a radial bearing surface provided on the sub-bearing and slidably supporting a radial surface of the drive shaft; and

a thrust receiving surface that slidably supports a thrust surface of the drive shaft,

between the thrust surface and the thrust receiving surface: a contact point at which the thrust surface is brought into contact with the thrust receiving surface in a curved surface, and a slit that continuously increases from the contact point toward a radially outer side.

2. The compressor of claim 1,

an oil storing space for storing lubricating oil is formed radially outside the thrust receiving surface.

3. The compressor of claim 2,

the hermetic container has an oil storage space inside,

and an oil pump connected to a pump insertion shaft formed on the drive shaft at a lower portion of the sub-bearing, for sucking up the lubricating oil in the oil storage space by rotation of the drive shaft,

a radial oil groove extending in a radial direction of the drive shaft is provided between the thrust surface and the thrust receiving surface,

the lubricating oil sucked up by the oil pump and passing through the radial oil groove is stored in the oil storage space.

4. The compressor of claim 3,

the compressor includes an auxiliary frame disposed in the hermetic container and provided with the auxiliary bearing,

the oil pump is attached to the sub-frame, an oil discharge flow path for discharging the lubricating oil in the oil storage space from an outlet to the oil storage space is formed by a groove and a hole formed in one or both of attachment surfaces of the sub-frame and the oil pump, and a throttle flow path serving as a flow path resistance is formed in the middle of the oil discharge flow path.

5. The compressor of claim 4,

the outlet of the oil discharge flow path is disposed below the oil storage space, and the upper end of the oil storage space is disposed above the radial oil groove.

6. A compressor according to any one of claims 3 to 5,

the drive shaft is provided at an upper end thereof with an eccentric shaft eccentric from an axial center of the drive shaft,

the radial oil groove is formed to extend in an eccentric direction, which is a direction connecting the axial center of the eccentric shaft to the axial center of the drive shaft.

7. The compressor of claim 6,

the radial oil groove is disposed on the thrust surface of the drive shaft in a range of 0deg to 45deg in a rotational direction of the drive shaft from the eccentric direction.

8. A compressor according to any one of claims 3 to 7,

an annular member having a through hole in a central portion into which the pump insertion shaft is inserted is disposed below the thrust surface, and the thrust receiving surface is formed on an upper surface side of the annular member.

9. The compressor of claim 8,

the annular member is a profile member of the oil pump.

10. The compressor of claim 8,

the annular member is a bottom plate fixed to a lower side of the auxiliary frame on which the auxiliary bearing is provided.

11. The compressor according to any one of claims 8 to 10,

the radial outer side of the thrust receiving surface of the annular member is formed by an inclined surface inclined downward as it faces outward, thereby forming the oil storage space.

12. The compressor according to any one of claims 8 to 11,

an inner peripheral portion of the thrust receiving surface on the upper surface side of the annular member, which is formed by the through hole, is a chamfered portion having a curvature radius Rp 0.

13. The compressor of claim 8,

the ring-shaped member is a member obtained by grinding the surface of a quenched steel strip.

14. The compressor of any one of claims 3 to 13,

the plurality of radial oil grooves are formed on the thrust receiving surface.

15. The compressor according to any one of claims 2 to 6,

the oil storage space is formed by an inclined surface inclined upward as the thrust surface of the drive shaft is directed outward in the radial direction.

16. The compressor of any one of claims 1 to 15,

a chamfered portion that comes into contact with the thrust receiving surface at the contact point is formed in a radially outer peripheral portion of the thrust surface of the drive shaft, and a curvature radius Rs1 of the chamfered portion is formed in a circular arc angle range of less than 90 degrees.

17. The compressor of claim 16,

the radius of curvature Rs1 of the chamfered portion at the radially outer peripheral portion of the thrust surface is larger than the radius of curvature Rp0 at the inner peripheral side of the thrust receiving surface, that is, Rs1 > Rp0 is provided.

18. The compressor of any one of claims 1 to 17,

the drive shaft is provided with:

an oil supply longitudinal hole extending in the axial direction of the drive shaft, through which lubricating oil flows; and

and a thrust oil supply lateral hole that communicates with the oil supply longitudinal hole at a position lower than the thrust surface and extends in a radial direction of the drive shaft, and that supplies the lubricating oil between the thrust surface and the thrust receiving surface.

19. The compressor of claim 18,

the drive shaft is provided with:

a radial oil supply lateral hole that communicates with the oil supply longitudinal hole at a position above the thrust surface, extends in a radial direction of the drive shaft, and supplies the lubricating oil between the radial surface and the radial receiving surface; and

an axial oil groove which is communicated with the radial oil supply transverse hole, is formed on the outer peripheral surface of the driving shaft, and extends along the axial direction of the driving shaft,

the axial oil groove faces the radial receiving surface, and a length of the drive shaft in the axial direction is longer in a region of the outer peripheral surface of the drive shaft facing the radial receiving surface, the region being located above the axial oil groove than in a region located below the axial oil groove.

20. A compressor, wherein,

the compressor is provided with:

a compression mechanism unit disposed in the closed container;

a motor unit that drives the compression mechanism unit;

a drive shaft that transmits a driving force of the motor unit to the compression mechanism unit;

a main bearing supporting an upper portion of the drive shaft;

a sub-bearing supporting a lower portion of the drive shaft;

a thrust receiving surface that slidably supports a thrust surface of the drive shaft; and

a radial bearing surface that slidably supports a radial surface of the drive shaft,

the drive shaft is provided with:

an oil supply longitudinal hole extending in the axial direction of the drive shaft, through which the lubricating oil flows; and

and a thrust oil supply lateral hole that communicates with the oil supply longitudinal hole at a position lower than the thrust surface and extends in a radial direction of the drive shaft, and that supplies the lubricating oil between the thrust surface and the thrust receiving surface.

Technical Field

The present invention relates to a compressor used as one of components of a refrigeration cycle apparatus.

Background

A scroll compressor is one of the components of a refrigeration cycle apparatus such as an air conditioner, and includes: a compression mechanism portion having an oscillating scroll and a fixed scroll engaged with each other; a motor unit that drives the compression mechanism unit; and a drive shaft that transmits the driving force of the motor unit to the compression mechanism unit. The drive shaft is rotatably supported by main bearings and sub bearings provided above and below the motor unit. When the drive shaft is rotated by the motor, the orbiting scroll provided on the eccentric shaft portion of the upper end portion of the drive shaft revolves. Thereby, the refrigerant is compressed in the compression chamber between the orbiting scroll and the fixed scroll provided in the compression mechanism portion. When the refrigerant is compressed in the compression mechanism, a radial gas load acts on the drive shaft, and the gas load is supported by the main bearing and the sub-bearing. In addition, the sub-bearing supports the rotation of the drive shaft and supports the weight of the drive shaft in the vertical downward direction.

In such a scroll compressor, a ball bearing is often used as a sub bearing in order to simultaneously support both a load in a radial direction (hereinafter, referred to as a radial load) and a load in a thrust direction (hereinafter, referred to as a thrust load) (see, for example, patent document 1).

However, the ball bearing is expensive, and the inner ring and the rolling ball, and the outer ring and the rolling ball receive the load in point contact, respectively, and therefore, there are various problems such as poor long-term reliability. As a countermeasure, there is a scroll compressor in which a sliding bearing is applied to a sub-bearing (for example, see patent document 2).

In the scroll compressor described in patent document 2, the sub-bearing as the sliding bearing is constituted by a radial bearing and a thrust bearing which support a radial load and a thrust load independently from each other. The thrust surface provided at the lower end portion of the drive shaft is received by the thrust receiving surface provided at the sub-bearing, and the radial surface provided at the sub-shaft portion of the drive shaft is received by the radial receiving surface provided at the sub-bearing.

Patent document 1: japanese laid-open patent publication No. H04-241786

Patent document 2: japanese patent No. 4356375

Generally, a drive shaft of a scroll compressor is subjected to a compression load and a centrifugal force during operation, and a large load is applied in a radial direction. Therefore, the axial center of the drive shaft bends while inclining with respect to the central axis of the compressor. The central axis of the compressor is a shaft extending in the vertical direction. The main shaft portion and the auxiliary shaft portion of the drive shaft rotate while being tilted with respect to the main bearing and the auxiliary bearing, respectively. As in patent document 1, when a ball bearing is used for the sub bearing of the scroll compressor, the inclination of the drive shaft is absorbed by the gap between the rolling ball and the inner ring and the gap between the rolling ball and the outer ring, and thus it is easy to ensure the parallelism between the drive shaft and the sub bearing. However, the ball bearing is inferior in cost and long-term reliability as described above.

As in patent document 2, when a sliding bearing is used for the sub-bearing, although it is advantageous in terms of cost and long life, there are problems as follows: the drive shaft rotating while being inclined is in contact with one side of the thrust receiving surface, so that the local hertzian stress is increased, and the sliding state on the thrust receiving surface becomes severe. However, in patent document 2, no consideration is given to the problem of one-side contact with respect to the thrust receiving surface.

Disclosure of Invention

The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a compressor in which a sliding bearing is used as a sub-bearing, and which can ensure a good sliding state of a thrust receiving surface.

The compressor according to the present invention includes: a compression mechanism unit disposed in the closed container; a motor unit that drives the compression mechanism unit; a drive shaft for transmitting the driving force of the motor to the compression mechanism; a main bearing supporting an upper portion of the drive shaft; a sub-bearing supporting a lower portion of the drive shaft; a radial bearing surface provided on the sub-bearing and supporting a radial surface of the drive shaft to be slidable; and a thrust receiving surface that slidably supports the thrust surface of the drive shaft, and between the thrust surface and the thrust receiving surface, a contact point at which the thrust surface and the thrust receiving surface are brought into contact with each other in a curved surface and a slit that continuously increases from the contact point toward a radially outer side are provided.

According to the present invention, a favorable sliding state of the thrust receiving surface can be ensured.

Drawings

Fig. 1 is a vertical sectional view schematically showing a sectional structure of a scroll compressor according to embodiment 1 of the present invention.

Fig. 2 is a diagram showing a main part of a scroll compressor according to embodiment 1 of the present invention.

Fig. 3 is an explanatory view of a bent state of the drive shaft of the scroll compressor according to embodiment 1 of the present invention in the Z-X cross section and a position of the radial oil groove in the circumferential direction.

Fig. 4 is an explanatory diagram of a state of deflection in the Y-Z cross section and a position of arrangement in the circumferential direction of the radial oil groove of the drive shaft of the scroll compressor according to embodiment 1 of the present invention.

Fig. 5 is an explanatory view of the load acting on the drive shaft and the direction in which the load acts in the scroll compressor according to embodiment 1 of the present invention.

Fig. 6 is a diagram showing a modification 1 of the scroll compressor according to embodiment 1 of the present invention.

Fig. 7 is a diagram showing a modification 2 of the scroll compressor according to embodiment 1 of the present invention.

Fig. 8 is a diagram showing a modification 3 of the scroll compressor according to embodiment 1 of the present invention.

Fig. 9 is a diagram showing a main part of a scroll compressor according to embodiment 2 of the present invention, and is a schematic diagram showing a portion closer to a lower end than a sub bearing in an enlarged manner.

Fig. 10 is a diagram showing a main part of a scroll compressor according to embodiment 3 of the present invention, and is a schematic diagram showing a portion closer to a lower end than a sub bearing in an enlarged manner.

Detailed Description

Hereinafter, a scroll compressor according to an embodiment of the present invention will be described with reference to the drawings as an example of the compressor. Here, including fig. 1, in the following drawings, the same or corresponding portions are denoted by the same reference numerals, and are used in common throughout the embodiments described below. The embodiments of the constituent elements expressed throughout the specification are merely examples, and are not limited to the embodiments described in the specification.