JP3012063B2 - Thrust ball bearings - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thrust ball bearing which is used in a scroll compressor or the like and supports a revolving member such as a revolving scroll member so as not to rotate.

[0002]

2. Description of the Related Art A scroll compressor comprises a revolving scroll member 51 and a stationary scroll member 5 as shown in FIG.
2 are provided with spiral partition walls 53 and 54, respectively.
The compression chamber 55 formed between the revolving scroll members 5
The compression operation is performed by changing the volume along with one revolution.

The revolving scroll member 51 revolves around the revolving radius E without rotation, and a ball 56 is interposed between the revolving scroll member 51 and the fixed frame 57 to prevent the revolving and to revolve. Let me. The orbiting scroll member 51 and the fixed frame 57 are provided with a concave portion 58 for restraining the moving range of the ball 56, and the diameter of the concave portion 58 is substantially equal to the orbital radius E so that the ball 56 can roll freely in a circular orbit. Designed equally.

[0004] Instead of the recess 58, the raceway grooves 59 groove cross section of the arcuate annular as shown in FIG. 12, the radius of revolution E
A track formed with a track diameter e equal to the following has been proposed (for example, JP-A-55-155916).

[0005]

SUMMARY OF THE INVENTION In the example of FIG.
A large axial load acts on the orbiting scroll member 51 due to the compressed gas pressure in the compression chamber 55, and this load is applied to the contact surface between the ball 56 and the bottom surface of the recess 58. However, since this contact state is a point contact between the sphere and the plane, the contact pressure per unit area is large, so that there is a problem that the wear and rolling fatigue are remarkable and the bearing life is shortened.

In the example shown in FIG. 12, since the inner surface of the raceway groove 59 has an arc shape, the contact area of the ball 56 with the raceway surface is increased, and the life is greatly improved. However, it is very difficult to directly process such an annular raceway groove 59 having an arc-shaped cross section on the orbiting scroll member 51 and the fixed frame 57, and therefore, there is a problem that productivity is low and manufacturing cost is high. .

It is an object of the present invention, a thrust ball bearing odor performing support revolving Te is possible to easily in manufacturing.

[0008]

SUMMARY OF THE INVENTION A thrust ball bearing according to the present invention is characterized in that a pair of ring-shaped orbital rings on which balls are interposed are manufactured separately from a revolving member and a fixed member, and mounted on the revolving member and the fixed member. It is. Each bearing ring is optional
The cross-sectional shape of the circumferential portion is rectangular, and both races
Orbital grooves on each of the opposing surfaces to roll the balls in a ring
Are provided at a plurality of locations spaced apart in the circumferential direction .

According to a second aspect of the present invention, there is provided a thrust ball bearing comprising: a ring-shaped race; a plurality of raceway groove forming members having respective raceway grooves formed therein; and a plurality of counterbore portions in which the raceway groove forming members are respectively embedded. And a ring-shaped bearing ring main body having the following.

[0010] Thrust ball bearing according to claim 3, Ru der one provided a ring-shaped retainer for holding the entire periphery of the ball retainer state. The thrust ball bearing according to claim 4 is a ring-shaped orbit.
The ring is composed of the raceway groove forming member and the raceway ring main body as described above.
Raceway groove forming member and raceway ring
The materials of the main body are different from each other.

[0011]

According to this configuration, when the revolving member revolves, the rolling path of the ball interposed between the revolving member and the fixed member is restrained by the local annular raceway grooves in the races of both members. As a result, rotation of the revolving member is prevented.
You. Trajectories Michimizo is a ring-shaped groove, to form a dedicated bearing ring separate from the revolving member and the fixed member can be easily manufactured.

When the ring-shaped bearing ring is divided into a raceway groove forming member and a bearing ring main body, it is not necessary to heat-treat the ring-shaped bearing ring body, so that heat treatment deformation does not occur and accuracy is improved. Can be achieved.

When the retainer is provided, when the ball is incorporated into the bearing ring, the ball can be incorporated while being retained by the retainer. As a result, all balls will be incorporated in the same phase into each raceway groove of both races,
The phase adjustment work of the ball at the time of assembling becomes unnecessary.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. This embodiment is an example applied to a scroll compressor, in which a thrust ball bearing 1 includes a fixed frame 2 and a revolving scroll member 3 serving as a fixed member and a revolving member, respectively.
And is provided between them.

The orbiting scroll member 3 has a cylindrical portion 3a protruding from the center thereof rotatably fitted to a drive shaft 4 via a bearing 5 such as a needle bearing. (Not shown), and is driven to revolve around a revolving center Q which is the axis of the rotating shaft with a revolving radius E.
Therefore, the orbiting scroll member 3 performs an orbital motion with the orbital radius E around the orbital center Q together with the drive shaft 4.

A fixed scroll member (not shown) facing the upper surface of the revolving scroll member 3 is provided in a housing 6 integral with the fixed frame 2, and the revolving scroll member 3 and the fixed scroll member are provided respectively. between the spiral-shaped partition (not shown), the compression chamber of the scroll compressor is constructed as in the example of FIG. 11.

The thrust ball bearing 1 is composed of a pair of facing ring-shaped races 7, 7 mounted on the fixed frame 2 and the revolving scroll member 3, and a ball 8 interposed between the races 7, 7. Be composed. Each of the bearing rings 7 is fitted in an annular bearing ring mounting groove 9 formed in the fixed frame 2 and the revolving scroll member 3 in a fitted state. As shown in FIG. 2, the bearing ring 7 is provided with a detent
When the projection 10 engages with a recess (not shown) in the raceway mounting groove 9, the angle is fixed to the fixed frame 2 and the orbiting scroll member 3.

On the opposing surfaces of the pair of races 7, annular race grooves 11 for rolling the balls 8 are equally arranged at a plurality of positions in the circumferential direction. Each of the raceway grooves 11 is formed in an arc-shaped cross section having a slightly larger radius of curvature r than that of the ball 8, and the diameter e of the circumferential raceway along the groove bottom is substantially equal to the orbital radius E of the orbiting scroll member 3. Set equal.

The relationship between the diameter e of the circumferential orbit of the raceway groove 11 and the radius of curvature r of the groove cross section is appropriately set according to the application location. For this reason, in the annular raceway groove 11, there may be a case where the inner peripheral edge 11a of the opening becomes one point continuously as shown in FIG. 3 and a case where the inner peripheral edge 11a of the opening is separated as shown in FIG.

The operation of the above configuration will be described. The orbiting scroll member 3 orbits with an orbital radius E by the drive of the drive shaft 4. At this time, the fixed frame 2 and the revolving scroll member 3 are engaged via the ball 8 interposed between the races 7, 7, and the rolling range of the ball 8 is within the local annular raceway groove 11. , The revolving scroll member 3 is prevented from rotating. That is, each of the balls 8 moves along with the orbital movement of the orbiting scroll member 3,
7 has a diameter e equal to the orbital radius E in the annular raceway groove 11.
Roll in a circular orbit. Therefore, the revolving scroll member 3 revolves while maintaining a constant angular relationship with the fixed frame 2 at all times, and the compression operation of the scroll compressor is performed by such an operation.

The revolving scroll member 3 is compressed by the compressed gas pressure.
Has a large axial load, which is received at the contact surface between the ball 8 and each of the races 7,7. At this time, since the inner surface of the raceway groove 11 is formed in an arc-shaped cross section, the contact area with the ball 8 is large, so that wear and rolling fatigue hardly occur, and the bearing life is improved.

The raceway groove 11 is an annular groove having an arc-shaped cross section which is relatively difficult to machine. However, since the raceway groove 11 is formed on the raceway rings 7, 7 which are simply shaped ring-shaped parts, the orbiting scroll member 3 or the like having a complicated shape is required. Processing can be performed more easily than when the track groove 11 is processed directly on the fixed frame 2.

The raceway groove 11 may be formed by cutting out a raceway material made of a steel plate. Alternatively, a forming method such as press working or sintering may be employed as follows.

In the case of press working, a recessed shape of the raceway groove 11 is formed by press working or forging on a ring-shaped raceway material made of a steel plate, and thereafter, as shown in a cross section in FIG. The surface is hardened by carburizing or induction hardening. In order to finish the inner surface of the raceway groove 11, a diameter slightly larger than that of the ball 8 used as a bearing (the raceway groove 1) is used.
(A radius corresponding to the design curvature of the groove cross section of No. 1) is used, and the ball and the lapping agent are arranged in the raceway groove 11 so that the pair of opposed raceways 7 revolves in the same way as in use. Rub while revolving at radius E. This allows
The raceway groove 11 can be finished to a predetermined sectional shape.

In the case of the working method by sintering, the orbital ring 7 is formed into a shape having the orbital groove 11 using an iron-based sintered alloy. Thereafter, the inner surface of the raceway groove 11 is carburized,
Increase hardness. Finishing after carburization is performed by rubbing using a polishing ball as in the case of the above-described press. As described above, by using the press or the sintering, the workability is improved as compared with the shaving, and the manufacturing cost can be reduced.

FIG. 6 shows another embodiment. In this example, a ring-shaped raceway ring 7 is formed by a plurality of raceway groove forming members 12 in which respective raceway grooves 11 are respectively formed, and a ring-like raceway provided with a counterbore portion 13 in which each of the raceway groove forming members 12 is embedded. Wheel body 1
4. The bearing ring forming member 12 uses a commonly used bearing steel or the like, and performs hardening treatment not only on the surface but also on the core by so-called hardening. The raceway body 14 does not require a surface hardening treatment, and various materials can be used. For example, an aluminum alloy such as hard anodized aluminum, an aluminum casting, or the like can be adopted, whereby the manufacture of the bearing ring body 14 having the counterbore 13 can be easily performed.

In the case of this configuration, the raceway body 14 does not require heat treatment for surface hardening, and thus differs from the above-mentioned embodiments in which the entire raceway ring 7 is heat-treated. No significant heat treatment deformation occurs.
Therefore, the height accuracy of the raceway groove 11 of each part is improved. In particular, when the width dimension B is smaller than the outer diameter of the bearing ring 7, the above-described problem of the warpage of the ring shape is likely to occur. In such a case, this embodiment is effective.

As shown in FIG. 7, the raceway forming member 12 may have a flat portion 12a formed on the outer periphery thereof, thereby preventing rotation in the counterbore recess 13 and preventing the fitting surface from being worn. .

FIGS. 8 and 9 show still another embodiment. In this example, a ring-shaped holder 15 for holding the ball 8 around the entire circumference is provided. The retainer 15 has the same configuration as the retainer provided in a normal flat seat type thrust ball bearing, and is capable of retaining the ball 8 in each pocket in a retaining state. The material of the retainer 15 is a press-formed product of an iron plate in this example, but may be a resin or a brass casting.

By providing the retainer 15 in this manner, the work of assembling the ball 8 becomes easy. That is, in this type of thrust ball bearing, it is necessary to match the phases of the balls 8 to all the raceway grooves 11 of the two races 7, 7 at the time of assembly. Therefore, if the balls 8 are incorporated one by one, Difficult phase alignment work. However, when the retainer 15 is provided as in this embodiment, by incorporating the balls 8 in a state of being retained by the retainer 15, all the balls 8 are incorporated in the respective track grooves 11 in the same phase. Become. Therefore, the phase matching operation is not required, and the assembling operation is simplified.

The retainer 15 can be provided in each of the above embodiments. For example, in the embodiment in which each track groove 11 in FIG. 6 is provided in the individual track groove forming member 12, as shown in FIG. 10, a retainer 15 may be provided in the same manner as described above.

[0032]

Thrust ball bearing of Effects of the Invention The present invention, because that was to be attached to these revolving member or the like prepared separately from the ring rail wheels revolving member or a fixing member that forms a trajectories Michimizo,
Processed easily is performed, there is an effect that cost reduction can be achieved.

In the thrust ball bearing of the second aspect, the ring-shaped bearing ring is composed of a plurality of track groove forming members each having a respective track groove, and a ring-shaped bearing ring main body having a counterbore. Accuracy can be improved without causing significant heat treatment deformation.

In the thrust ball bearing according to the third aspect of the present invention, the retainer for holding the ball on the entire circumference in a retaining state is provided. it can. For this reason, all the balls of both races are assembled in the same phase in each raceway groove, so that the phase matching operation becomes unnecessary and the installation operation is simplified.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a state in which a thrust ball bearing according to one embodiment of the present invention is incorporated in a scroll device.

FIG. 2 is a perspective view of the bearing ring.

FIG. 3 is a partially enlarged sectional view of a modified example of a bearing ring.

FIG. 4 is a partially enlarged cross-sectional view of another modified example of a bearing ring.

FIG. 5 is a partially enlarged sectional view of still another modification of the bearing ring.

FIG. 6 is a partially exploded perspective view of another embodiment of the present invention.

FIG. 7 is a partial plan view of a bearing ring according to still another embodiment of the present invention.

FIG. 8 is a sectional view showing a state in which a thrust ball bearing according to still another embodiment of the present invention is incorporated in a scroll device.

FIG. 9 is a perspective view of the retainer.

FIG. 10 is a partial sectional view showing still another embodiment of the present invention.

FIG. 11 is a partial sectional view showing a relationship between a conventional thrust ball bearing and a scroll device.

FIG. 12 is a partial sectional view of another conventional example.

[Explanation of symbols]

1 ... thrust ball bearing, 2 ... fixed frame (fixed member),
3 ... revolving scroll member (revolving member), 4 ... drive shaft, 7
… Track ring, 8… ball, 11… track groove, 12… track groove forming member, 13… counterbore part, 14… track ring body, 15… retainer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16C 19/10 F16C 33/58 F04C 18/02 311

Claims (4)

(57) [Claims] 1. A pair of ring-shaped orbital rings which are mounted on a revolving member and a fixed member which revolve with each other and face in the axial direction are provided, and these orbital rings are arranged laterally of an arbitrary circumferential portion.
The cross-sectional shape is rectangular, and on the opposing surfaces of both races,
The raceway grooves for rolling each ball in a ring are spaced in the circumferential direction.
Thrust ball bearings provided at multiple locations separated by 2. A ring-shaped orbit having a plurality of raceway groove forming members in which respective raceway grooves are formed, and a plurality of counterbore portions in which the raceway groove forming members are respectively embedded. The thrust ball bearing according to claim 1, comprising a main body. 3. The thrust ball bearing according to claim 1, further comprising a ring-shaped retainer for retaining a ball around the entire circumference in a retaining state. 4. The material of the raceway groove forming member and the raceway body.
3. The thrust ball shaft according to claim 2, wherein
Receiving.