JPH08296654A - Thrust ball bearing for scroll machine - Google Patents

Abstract

PURPOSE: To improve the lubricating performance by piercing small holes for distributing the lubricant at a plurality of parts on the circumference of a ring- shaped bearing washer to reduce the fretting wear between the bearing washer and its fitting member. CONSTITUTION: A turning side bearing washer 13 is fitted to a turning scroll member 11, and a fixed side bearing washer 15 is fitted to a fixed frame 12. A ball is rotated along a raceway groove 17. The turning side bearing washer 13 and the fixed side bearing washer 15 are eccentrically moved, and the quantity of eccentricity is two times the diameter of the pitch circle of the raceway groove 17. The washers 13, 15 are of the same shape, and small holes 16 for distributing the lubricant are pierced at appropriate intervals such as the equal intervals at a plurality of parts on the inner and outer circumferential sides on the circumference of the washers 13, 15. The small holes are formed in the center of the pitch circle of a plurality of raceway grooves 17 formed on the circumference of the ring-shaped bearing washers 13, 15. Thus, more lubricant is distributed than the small holes for distributing the lubricant, and the fretting wear to be generated between a counter fitting member and the back surface of the bearing washer can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in thrust ball bearings for scroll machines such as scroll compressors for air conditioners.

[0002]

2. Description of the Related Art In a scroll compressor, as shown in FIG. 4, a spiral partition 5 is provided on an orbiting scroll member 3 which is eccentrically orbitally rotated by a shaft 2 which is rotationally driven by a motor 1, and a fixed scroll member 4 which is provided opposite to the orbiting scroll member 3. , 6 are provided respectively, and the volume of the compression chamber 7 formed between the both partition walls 5, 6 is changed in accordance with the orbit of the orbiting scroll member 3, whereby the fluid (refrigerant gas or the like) in the compression chamber 7 is compressed. It is a thing.

A thrust ball bearing a is generally used between the orbiting scroll member 3 and a fixed frame 4'which is integrally fixed to the fixed scroll member 4. In this thrust ball bearing a, as shown in FIG. 4, a pair of ring-shaped orbital rings 9 and 10 with balls 8 interposed in orbital ring mounting grooves 3a and 4a formed in the orbiting scroll member 3 and the fixed frame 4'are provided. I am wearing it and using it.

Each of the raceways 9 and 10 is made of a press-formed product such as a steel plate, and on their opposing surfaces, annular raceway grooves 9a and 10a for rolling the balls 8 are formed at a plurality of positions in the circumferential direction at equal intervals. It is molded. The raceway grooves 9a, 10a are formed such that the groove cross section has an arcuate cross section having a slightly larger radius of curvature than the ball 8, and the diameter of the circular orbit along the groove bottom is equal to the orbiting radius of the orbiting scroll member 3. There is.

[0005]

In the thrust ball bearing used in the scroll compressor, the pressure generated in the process of compressing the fluid acts as an axial load on the orbiting scroll member. A function of smoothing the eccentric motion while preventing the rotation of the scroll member is required.

Conventional thrust ball bearings for scroll machines, when used in applications where an axial load is applied,
Fretting wear may occur between the bearing races and the orbiting scroll member and fixed scroll member to which the bearing races are attached, but this countermeasure is not sufficient.

Therefore, the present invention provides a thrust ball bearing for a scroll machine which can reduce the fretting wear between the bearing ring which performs an eccentric motion while receiving an axial load and its mounting member and can improve the lubricating performance. The purpose is to

[0008]

In order to achieve the above object, the present invention provides a pair of ring-shaped orbits which are mounted in orbital ring mounting grooves formed in an orbiting scroll member and a fixed frame which eccentrically rotate with respect to each other. In a thrust ball bearing for a scroll machine composed of a ring and balls interposed between a pair of race rings, a small hole for lubricant distribution is passed through at a plurality of locations on the circumference of the ring-shaped race ring. Formed.

The small hole for circulating the lubricant may be formed in the center of the pitch circle of a plurality of raceway grooves formed on the circumference of the ring-shaped raceway ring.

Further, a flat surface portion may be provided on the back surface of the plurality of raceway grooves formed on the circumference of the ring-shaped raceway ring so as to come into contact with the groove bottom surface of the raceway ring mounting groove of the counterpart mounting member.

Further, the entire surface of the bearing ring may be surface-treated.

[0012]

[Function] Since a small hole for lubricant distribution is formed at a plurality of locations on the circumference of the bearing ring, the lubricant flows through the small hole and enters the back side of the bearing ring, Fretting wear that occurs between the mating attachment member and the back surface of the bearing ring can be reduced. Further, by providing the flat portion on the back surface of the bearing ring, the contact state between the bearing ring and the counterpart mounting member is improved, and fretting can be reduced.
Further, by surface-treating the entire surface of the bearing ring, it is possible to assist the lubrication of the bearing and reduce the fretting wear of the back surface of the bearing ring.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below with reference to the embodiments of the drawings. FIG. 1 is a schematic vertical cross-sectional view showing a mounting example of a thrust ball bearing for a scroll machine according to an embodiment of the present invention, in which 11 is an orbiting scroll member, 12 is a fixed frame, 13 is an orbiting wheel, and 14 is a ball. , 15 are fixed-side bearing rings.

The bearing rings 13 and 15 have the same shape, and the shape of one of the bearing rings 13 is shown in FIGS. 2A and 2B in a front view and a sectional view. Small holes 16 for lubricant circulation are formed at a plurality of positions on the inner circumference side and the outer circumference side of the bearing ring 13 at appropriate intervals such as equal intervals. This small hole 16
It is also formed at the center of the pitch circle of the plurality of raceway grooves 17 formed on the circumference of the ring-shaped raceway ring 13. The same applies to the fixed-side bearing ring 15.

Further, as shown in FIG. 3, bearing rings 13, 1 are used.
On the back surface of the plurality of raceway grooves 17 formed on the circumference of 5,
Orbital ring mounting groove 11a of the counterpart mounting member 11, 12;
A flat portion 18 is provided that abuts the bottom surface of the groove 12a.

It is also possible to perform surface treatment (for example, Parker treatment) on the entire surfaces of the bearing rings 13 and 15.
This surface treatment is performed to assist lubrication in the contact portion between the back surface of the bearing ring and the mating attachment member and to reduce fretting wear.
Appropriate surface treatment that can achieve this purpose can be applied.

The orbiting ring 13 is attached to the orbiting scroll member 11, and the fixed orbiting ring 15 is attached to the fixed frame 12. The ball 14 rotates along the track groove 17. The orbiting ring 13 and the stationary ring 15 are eccentrically moved, and the eccentricity e (see FIG. 1) is twice the pitch circle diameter d of the raceway groove 17 shown in FIG. 2B.

The embodiment of the present invention has the above-described structure. In that embodiment, only the small hole 16 is combined, or the small hole 16 and the surface treatment are combined, or the small hole 16 and the surface treatment are combined. The small holes 16, the flat surface portion 18, and the surface treatment can be combined and implemented.

[0019]

According to the present invention, since the small holes for the lubricant flow are formed at a plurality of locations on the circumference of the bearing ring, the lubricant flows through the small holes and the bearing ring is formed. It is possible to reduce the fretting wear that occurs between the mating attachment member and the back surface of the bearing ring by penetrating into the back surface side of the. Further, by providing the flat portion on the back surface of the bearing ring, the contact state between the bearing ring and the counterpart mounting member is improved, and fretting can be reduced. Further, by surface-treating the entire surface of the bearing ring, it is possible to assist the lubrication of the bearing and reduce the fretting wear of the back surface of the bearing ring.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing an attachment example of a thrust ball bearing for a scroll machine according to an embodiment of the present invention.

FIG. 2A is a front view of a bearing ring according to an embodiment of the present invention, and FIG. 2B is a sectional view taken along line AA ′ of FIG.

FIG. 3 is an enlarged cross-sectional view showing a configuration example of a bearing ring according to an embodiment of the present invention and an attachment example to a counterpart member.

FIG. 4 is a schematic sectional view of a main part of a conventional scroll machine.

[Explanation of symbols]

 11 orbiting scroll member 12 fixed frame 13 orbiting ring raceway 14 ball 15 fixed side bearing ring 16 small hole 17 raceway groove 18 plane part

Claims (4)

[Claims] 1. A pair of ring-shaped race rings mounted in race ring mounting grooves formed in an orbiting scroll member and a fixed frame which rotate eccentrically with each other, and a ball interposed between the pair of race rings. A thrust ball bearing for a scroll machine, characterized in that in a thrust ball bearing for a scroll machine, small holes for lubricant distribution are formed at a plurality of locations on the circumference of a ring-shaped bearing ring. 2. A small hole for lubricant distribution is also formed at the center of the pitch circles of a plurality of raceway grooves formed on the circumference of a ring-shaped raceway ring. Thrust ball bearings for scroll machines described in. 3. A flat portion is provided on the back surface of the plurality of raceway grooves formed on the circumference of the ring-shaped raceway ring, the flat portion being in contact with the groove bottom surface of the raceway ring mounting groove of the counterpart mounting member. The thrust ball bearing for a scroll machine according to claim 1 or 2. 4. The thrust ball bearing for a scroll machine according to claim 1, wherein the entire surface of the bearing ring is surface-treated.