JP2002295480A - Ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent increase of vibration of a holder constituting a ball bearing and early deterioration of grease even when using the ball bearing in high temperature environment by high speed rotation. SOLUTION: An outside diameter face of the crown type retainer 7a made of a synthetic resin is brought close to an inside diameter face of an outer ring 3, and the holder 7a is rotatably supported by outer ring guide. As a result, even if each pocket is expanded by thermal expansion, the holder 7a is guided by the inside diameter face of the outer ring 3 and is rotated. Consequently, even if the holder 7a attempts to displace in the radial direction, its displacement is prevented by the inside diameter face of the outer ring 3, and the vibration of the holder 7a is not increased. Moreover, it is possible to prevent local contact of an inner face of each pocket and a rolling face of each ball 6 even if the ball bearing is rotated at a high speed by forming each pocket into a cylindrical face. As a result, the deterioration of grease and the increase of rotation torque can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball bearing to be incorporated in various rotating machinery such as an alternator, an electromagnetic clutch device for a compressor, a pulley support device, a water pump device, and an electric motor. In particular, the present invention prevents an increase in the vibration of the cage constituting the ball bearing and an early deterioration of the grease even when the ball bearing is used in a high-speed rotation and high-temperature environment.

[0002]

2. Description of the Related Art As a ball bearing for supporting various rotating parts, such as a bearing part of various rotating machinery as described above, a ball bearing 1 as shown in FIGS. The ball bearing 1 includes an outer ring 3 having an outer ring raceway 2 on an inner peripheral surface,
An inner ring 5 having an inner ring raceway 4 on the outer peripheral surface is arranged concentrically,
A plurality of balls 6 are provided between the outer raceway 2 and the inner raceway 4 so as to roll freely. In the illustrated example, both the outer raceway 2 and the inner raceway 4 are of a deep groove type. The plurality of balls 6 are rollably held in pockets 8 provided in a holder 7. The outer peripheral edges of the seal plates 10 and 10 are engaged with engaging grooves 9 and 9 formed on the inner peripheral surfaces of both ends of the outer ring 3 over the entire periphery.

[0003] Each of these seal plates 10 and 10 is formed in a ring shape by reinforcing a resilient material 12 such as rubber or the like with a metal core 11 formed of a metal plate such as a steel plate in a ring shape. Formed. The outer peripheral edge of the elastic member 12 projects outward in the radial direction (the vertical direction in FIG. 7) slightly more than the outer peripheral edge of the cored bar 11. It is locked. On the other hand, the inner peripheral edge of the elastic member 12 is sufficiently protruded radially inward from the inner peripheral edge of the cored bar 11, and the protruding portion forms the seal lip 13. The edge of the seal lip 13 is slidably brought into contact with the side walls of the seal grooves 14 formed on the outer peripheral surfaces of both ends of the inner ring 5.

[0004] The retainer 7 is called a crown-type retainer, and the whole is integrally formed as shown in FIG. 9 by injection molding of synthetic resin. Such a retainer 7
The pockets 8 for holding the balls 6 (see FIGS. 7 to 8) in a freely rolling manner are provided at a plurality of locations in the circumferential direction of the annular main portion 15. In addition, each of these pockets 8, 8
9A, one side of a pair of elastic pieces 16, 16 arranged at an interval on one side in the axial direction of the main part 15, and one side in the axial direction (vertical direction in FIG. 9) of the main part 15 (FIG. (Upper surface of the elastic member), and spherical concave portions 17, 17 provided between the pair of elastic pieces 16, 16. As shown in FIGS. 8 (a) and 8 (b), one side surface of each of the elastic pieces 16 and the inner surfaces of the concave portions 17 and 17 have their curvature radius R calculated from the curvature radius r of the rolling surface of the ball 6. Are made slightly larger so that each of the balls 6 can be rolled freely.

[0005] Then, each ball 6 is attached to each elastic piece 1.
While elastically expanding the gap between the leading edges of 6, 16
It is pushed between the pair of elastic pieces 16, 16. The retainer 7 thus holds the ball 6 in each of the pockets 8,8.
Embracing each of these balls 6 with the outer raceway 2
And between the inner raceway 4 (see FIG. 7). By holding the balls 6 in the pockets 8 and 8 in this manner, the balls 7 are prevented from being displaced in the radial and axial directions by the balls 6 during operation. System.

In the ball bearing 1 having the above-described structure, the member on which the outer ring 3 is fixedly fitted and the member on which the inner ring 5 is fixedly fitted are freely rotatable based on the rolling of the balls 6. I do. At this time, the balls 6 revolve around the inner ring 5 while rotating. The cage 7 rotates around the inner ring 5 while being guided by the balls 6 at the same speed as the revolution speed of the balls 6. The seal plates 10 and 10 locked to the inner peripheral surfaces at both ends of the outer ring 3 prevent the grease sealed in the space 18 in which the balls 6 are installed from leaking to the outside, and to the outside. Foreign matter such as floating dust and water is prevented from entering the space 18 where the balls 6 are installed. The grease lubricates rolling contact portions between the outer raceway 2 and the inner raceway 4 and each ball 6.

In recent years, in the automobile industry, the volume of the engine room has been reduced due to the spread of front-wheel drive front-wheel drive vehicles for the purpose of reducing the size and weight and the demand for increasing the space in the passenger compartment. It is in. For this reason, miniaturization of automotive accessories (such as alternators and compressors) installed in such small-sized engine rooms,
The weight has been reduced. In addition, it is also required to ensure the performance centering on the output of each of these auxiliary devices while reducing the size and weight as described above. However, it is difficult to secure performance while reducing the size and weight. From these facts, in order to reduce the size and weight of each of the above-mentioned auxiliary machines, the operating speed of each of these auxiliary machines has been increased to compensate for a decrease in output of each of the auxiliary machines. Because of this,
The operating conditions of the ball bearings that support the rotating parts of these accessories are becoming faster and higher in temperature with such speeding.

For example, in the case of a ball bearing incorporated in an alternator for automobiles, the grease lubrication and inner ring rotation are used under severe conditions such that the maximum rotation speed is about 22000 min ^-1 (rpm) and the ambient temperature is about 200 ° C. at the maximum. . As a cage for a ball bearing used under such high-speed, high-temperature conditions, a crown-shaped cage 7 made of a heat-resistant synthetic resin as shown in FIGS. 7 to 9 described above is used. Things are being considered. The reason for this is that such a crown-shaped cage 7 made of heat-resistant synthetic resin is lighter in weight than metal-made corrugated press cages, and is superior in terms of self-lubrication, low friction characteristics, corrosion resistance, quietness, and the like. This is because the characteristics can be advantageously exhibited in a high-speed rotation and high-temperature environment.

[0009]

However, even when the crown-shaped retainer 7 made of such a synthetic resin having heat resistance is used, the following inconveniences occur under high-speed rotation and high-temperature environments. May occur. That is, the cage 7
Rises in temperature, the respective pockets 8, 8 of the retainer 7
Spread by thermal creep and centrifugal force. The gap t ₈ between the inner surface of each of the pockets 8 and the rolling surface of each ball 6 (see FIG. 8A) increases, and the play (movement amount) of the retainer 7 with respect to each ball 6 increases. Increase. As a result, the cage 7 that is guided and rotated by each of the balls 6
However, it becomes easy to be displaced in the radial and axial directions, and the vibration of the retainer 7 may increase. When the vibration of the retainer 7 increases in this way, the side surface of the retainer 7 on the main portion 15 side, the inner surface of the seal plate 10 locked to the end of the outer ring 3, and the main portion 15 side of the retainer 7 The outer diameter surface and the inner diameter surface of the outer ring shoulder 19 are more likely to come into contact with each other. When the cage 7 comes into contact with the seal plate 10 and the outer ring shoulder 19 in this manner, the grease receives a large shearing force at the contact portion, and the grease may be deteriorated early. In addition, when the cage 7 is worn due to the contact, the balance of the cage 7 is deteriorated, and the vibration is further increased. When the contact and the vibration are remarkable, the cage 7 and the seal plate 10 are used. May be damaged.

In addition, under high-speed rotation, the centrifugal force applied to the retainer 7 increases, and the retainer 7 is easily deformed radially outward. When the retainer 7 is deformed radially outward in this manner, the rolling surface of each ball 6 and the inner peripheral edge of each of the pockets 8 are more likely to come into contact with each other. As a result, the inner peripheral edge of each of the pockets 8 and 8 and the ball 6 come into local contact with each other, and the grease receives a significant shearing force at the contact portion, and the grease may be deteriorated early. or,
Such local contact not only increases the rotational torque of the ball bearing 1, but in a severe case, the cage 7 may be damaged.

In order to prevent such inconveniences, materials for the cage 7 include PPS (polyphenylene sulfide resin), PAI (polyamideimide resin), PBI (polybenzimidazole resin), and PI (polyimide resin).
It is conceivable to use a synthetic resin (engineering plastic material) having excellent heat resistance and mechanical strength, such as the above. Certainly, if such a synthetic resin is used, excellent characteristics can be exhibited even under a high-speed rotation and high-temperature environment, and the above-mentioned inconvenience may be prevented. However, simply changing the material of the retainer 7 in this manner does not fundamentally solve the above-described inconvenience, and may not be able to cope with the problem when used in a further high-speed rotation and high-temperature environment. There is. The ball bearing of the present invention has been invented in order to eliminate any of these disadvantages.

[0012]

The ball bearing according to the present invention comprises an outer ring having an outer raceway on an inner peripheral surface and an inner race having an inner raceway on an outer peripheral surface, as in the above-mentioned conventionally known ball bearings. A plurality of balls provided rotatably between the outer raceway and the inner raceway, and a retainer for rollingably holding the plurality of balls. Grease is sealed in the space in which the balls are installed to lubricate the rolling contact portions between the outer and inner raceways and the balls.

[0013] In particular, in the ball bearing of the present invention, the retainer is made of a heat-resistant synthetic resin, and has an annular main part and a plurality of main parts provided on one surface in the axial direction of the main part. It is a crown-shaped retainer comprising an elastic piece. Then, by making the outer diameter surface of the cage close to the inner diameter surface of the outer ring, the cage is rotatably supported by the outer ring guide.

[0014]

The ball bearing of the present invention having the above-mentioned structure increases the vibration of the cage constituting the ball bearing and deteriorates the grease at an early stage, even when used in a high-speed rotation and high-temperature environment. Can be prevented. That is, since the crown-shaped cage made of synthetic resin is rotatably supported by the outer ring guide, the temperature of the cage becomes high, the pockets are creeped, and the play amount of the cage against the balls is large. In this case, the retainer rotates while being guided by the inner diameter surface of the outer ring. For this reason, even if the cage is to be displaced in the radial direction, the cage is blocked by the inner diameter surface of the outer ring, so that the vibration of the cage does not increase. In addition, since the retainer is less likely to come into contact with other members, the grease is less likely to receive a large shear force, and the grease can be prevented from being deteriorated early.

By using the outer ring guide system for the cage in this way, the shape of each pocket of the cage can be a simple cylindrical surface. That is, in the case of the ball guide system,
In order to guide the retainer by the balls, in other words, to prevent radial displacement of the retainer by the balls, the shape of each pocket is changed into a spherical shape recessed in the circumferential direction of the retainer. It must be concave. On the other hand, when the cage is of the outer ring guide type as described above, the radial displacement of the cage is prevented by the inner diameter surface of the outer ring. Therefore, even when the shape of the pocket is a cylindrical surface, the displacement of the cage in the radial direction is prevented by the inner diameter surface of the outer ring, so that the vibration of the cage does not increase. If the shape of the pocket is a cylindrical surface in this way, even if the retainer is deformed radially outward due to centrifugal force, the inner surface of each pocket and each ball locally come into contact with each other. There is no. As a result, early deterioration of the grease due to such local contact can be prevented, and increase in the rotational torque can be prevented.

[0016]

1 and 2 show a first embodiment of the present invention corresponding to claim 1. FIG. The feature of the present invention is that even when the ball bearing 1a is used in a high-speed rotation and high-temperature environment, the vibration of the cage 7a constituting the ball bearing 1a is prevented from increasing and the grease is prevented from being deteriorated early. To this end, the guide system, shape, and structure of the retainer 7a have been devised. Since the configuration and operation of the other parts are the same as those of the conventional structure shown in FIG. 7, the same reference numerals are given to the same parts, and the duplicate description is omitted or simplified. The following description focuses on the characteristic portions of the above.

The above-mentioned retainer 7 constituting the ball bearing 1a of the present embodiment.
a is a ring-shaped main part 15 made of a heat-resistant synthetic resin, and a plurality of elastic members provided on one side in the axial direction of the main part 15 (the left side in FIG. 1 and the lower side in FIG. 2B). Piece 16, 1
6 and a crown type cage. Also, this cage 7
The retainer 7a is rotatably supported by the outer ring guide by bringing the outer diameter surface of a into close proximity to the inner diameter surface of the outer ring 3.
That is, by positioning the outer diameter surface of the main portion 15 constituting the retainer 7a close to the inner diameter surface of the outer ring shoulder portion 19, the positioning of the main portion 15 in the radial direction is performed. As shown in FIG. 2A, the inner surface of each pocket 8a of the retainer 7a is a simple cylindrical surface straight in the radial direction of the retainer 7a. Further, the distal ends of the elastic pieces 16, 16 facing each other are curved along the ball 6 so that the ball 6 does not fall out of the pocket 8a. Then, the distance W ₁₆ of the distal edge between the elastic pieces 16, 16, smaller than the diameter d ₆ of the balls 6, thereby achieving a positioning about the axial direction of the cage 7a.

The outer ring 3 is formed between the inner diameter surface of the outer ring shoulder 19 of the inner diameter surface of the outer ring 3 and the outer diameter surface of the main portion 15 of the outer diameter surface of the retainer 7a, Thickness t ₁₉ at normal temperature of the gap through which grease flows (inner diameter D of outer ring 3)
_3- the outer diameter D _7a ) of the cage 7 a
0.7 to 3.5% of the outer diameter D _7a Δt ₁₉ = (0.007 to
0.035) D _7a }. In the case where the thickness t ₁₉ exceeds 3.5%, in the gap becomes too large and the outer diameter surface of the cage 7a and the inner diameter surface of the outer ring 3, the retainer 7a is within a radial direction It becomes easy to rattle, and the vibration of the retainer 7a may increase. On the other hand, when the thickness t ₁₉ of the gap is less than 0.7%, the gap between the outer diameter surface of the cage 7a and the inner diameter surface of the outer ring 3 becomes too small,
Grease becomes difficult to spread to the parts to be lubricated. As a result, the lubrication state becomes severe, and the rotational torque of the ball bearing 1a may increase, or the temperature may increase significantly.

The thickness t _8a (= the inner diameter d _{8a of the} pocket 8a−ball) of the gap formed between the inner surface of each pocket 8a and the rolling surface of each ball 6 at normal temperature and through which lubricating oil flows. 6
Of the outer diameter d _6), preferably 2 to the outer diameter d ₆ of the balls 6
15% {t _8a = (0.02 to 0.15) d ₆ }.
If the thickness t _8a exceeds 15%, the gap between the inner surface of the pocket 8a and the rolling surface of the ball 6 becomes too large, and the retainer 7a tends to rattle in the axial direction. Therefore, the vibration of the retainer 7a may increase.
On the other hand, if the thickness t _8a is less than 2%, the gap between the inner surface of the pocket 8a and the rolling surface of the ball 6 becomes too small, and it becomes difficult for the grease to spread to the portion to be lubricated.
As a result, the lubrication state becomes severe, and the rotational torque of the ball bearing 1a may increase, or the temperature may increase significantly. The thickness of the retainer 7a in the radial direction and the width in the axial direction are regulated in consideration of the strength of the retainer 7a.

The material of the retainer 7a is the engineering plastic material described in the section of the problem to be solved, that is, PPS (polyphenylene sulfide resin), PAI (polyamide imide resin), PBI
(Polybenzimidazole resin), synthetic resin excellent in heat resistance and mechanical strength, such as PI (polyimide resin), can be used. Also, the outer ring 3, inner ring 5, ball 6,
Although the material of each member of the seal plates 10 and 10 is not particularly limited, if necessary, it is assumed that excellent characteristics can be exhibited even in a high-speed rotation and high-temperature environment. For example, the outer ring 3
And at least one of the inner rings 5 is M5
0, or made of heat-resistant stainless steel such as SUS440C or SUS420C, or heat-resistant metal such as molybdenum steel,
It is more preferable that the balls 6 are made of ceramic or bearing steel.

The ball bearing 1a of the present embodiment configured as described above has
Even when the ball bearing 1a is used under a high-speed rotation and high-temperature environment, it is possible to prevent the vibration of the cage 7a constituting the ball bearing 1a from increasing and prevent the grease from being deteriorated early. That is, since the crown-shaped retainer 7a made of synthetic resin is rotatably supported by the outer ring guide, the temperature of the retainer 7a becomes high, and the pocket 8a thermally creeps. Even if the amount of play with respect to
Is rotated by being guided by the inner diameter surface of the outer ring 3. Therefore, even if the retainer 7a is displaced in the radial direction, the displacement of the retainer 7a is prevented by the inner diameter surface of the outer ring 3, so that the vibration of the retainer 7a does not increase. Moreover, since the retainer 7a does not easily come into contact with the seal plate 10 or the like, the grease is less likely to receive a large shearing force, and the grease can be prevented from being deteriorated early. The inner surface of the outer ring 3 and the retainer 7
With respect to the outer diameter surface of the main portion 15a, a gap is formed uniformly over the entire circumference, and a sufficient grease oil film is formed in this gap. Therefore, the shearing force per unit area applied to the grease oil film is limited, and the durability of the grease can be ensured.

Further, by using the outer ring guide system for the retainer 7a, the shape of each pocket 8a of the retainer 7a can be a simple cylindrical surface. That is, in the case of the ball guide system, the cage 7 is guided by the balls 6 as in the conventional structure shown in FIGS. 7 to 9 described above, in other words, the displacement of the cage 7 in the radial direction. The shape of each pocket 8 is a spherical concave surface that is recessed in the circumferential direction of the retainer 7 in order to prevent the occurrence of the above. On the other hand, when the cage 7a is of the outer ring guide type as described above, the radial displacement of the cage 7a is prevented by the inner diameter surface of the outer ring 3. Therefore, even when the shape of the pocket 8a is a cylindrical surface, the displacement of the retainer 7a in the radial direction is prevented by the inner diameter surface of the outer ring 3, so that the vibration of the retainer 7a does not increase.
If the shape of the pocket 8a is cylindrical as described above, even if the retainer 7a is deformed radially outward due to centrifugal force, the inner diameter surface of each pocket 8a and the ball 6
Does not contact locally. As a result, early deterioration of the grease due to such local contact can be prevented, and increase in the rotational torque can be prevented. Further, a sufficient clearance is provided between the opening edge portions of both ends of each of the pockets 8a and the rolling surface of the ball 6 held in each of the pockets 8a, so that grease is taken into each of the pockets 8a. Effectively, the rotation torque can be prevented from increasing from this aspect as well.

Next, FIG. 3 also corresponds to claim 1.
5 shows a second example of the embodiment of the present invention. In this example
Also in the case, similarly to the first example of the above-described embodiment, the retainer
7b and the inner diameter surface of the outer ring 3 (see FIG. 1)
This allows the cage 7b to rotate freely by the outer ring guide.
I support it. And in the case of this example, the above-mentioned cage 7
b) One side in the axial direction of the main part 15 constituting {circle over (b)} in FIG.
Between the pockets 8a adjacent on the side｝ and in the circumferential direction
The through-holes 20 and 20 are formed in the inner surface and the outer surface of the main portion 15 respectively.
Through the outer surface of the main portion 15 and the outer surface.
Grease can be sent freely between the inner surface of the wheel 3
I have. The inner diameter d of the through holes 20₂₀Is the outer diameter d of the ball 6
₆ 10-30% ｛d of₂₀= (0.1-0.3) d₆ }When
are doing. In addition, this inner diameter d₂₀Is less than 10%,
It becomes difficult for grease to flow through the through holes 20, 20,
Parts to be lubricated (the outer diameter surface of the main part 15 and the inner diameter of the outer ring 3)
Between the surface and the surface)
I can't get it. On the other hand, the inner diameter d ₂₀Is over 30%
Is difficult to secure the strength of the retainer 7b.
Not only does the durability of the retainer 7b decrease, but also
There is also a possibility that the container 7b is easily damaged.

Further, at least one through hole 20 is provided in any portion between the adjacent pockets 8a, and more preferably, one through hole is provided in each of the portions. However, as long as the strength of the retainer 7b can be ensured, a plurality of the retainers 7b may be provided in the space as needed. In the case of the present example in which the through holes 20 are provided between the adjacent pockets 8a in this manner, the grease is applied between the inner diameter surface of the outer ring 3 and the outer diameter surface of the retainer 7b (the guide surfaces are not connected to each other). ) And lubrication performance is more easily secured. For this reason, the torque characteristics and the temperature rise characteristics can be further improved as compared with the case of the above-described first example. Other configurations and operations are the same as those of the above-described first example, and thus redundant description will be omitted.

Next, FIG. 4 shows a third example of the embodiment of the present invention, which also corresponds to claim 1. Also in the case of this example, as in the first example of the above-described embodiment, by making the outer diameter surface of the retainer 7c close to the inner diameter surface of the outer ring 3 (see FIG. 1), this retainer 7c is attached to the outer ring. It is rotatably supported by guidance. And in the case of this example, the above-mentioned cage 7
The concave grooves 21, 21 are provided on the outer diameter surface of the main portion 15 constituting c in a state of being continuous from one end edge in the axial direction of the main portion 15 to the other end edge. The cross-sectional shape of each of the concave grooves 21 and 21 is not limited to a trapezoidal shape as shown in the drawing, but is not shown, but is a rectangular shape, a curved shape such as a semicircle, and a trapezoidal shape having curved corners. Or it can be rectangular.

It is to be noted that each of the grooves 21 is provided at least in one of the portions between the adjacent pockets 8a, and more preferably one in each of these portions. Further, as long as the strength of the retainer 7c can be ensured, a plurality of the retainers 7c may be provided in the above-mentioned space portion as needed. In the case of the present embodiment in which the concave grooves 21 and 21 are provided between the adjacent pockets 8a as described above, it becomes easy to hold the grease on the outer diameter surface of the retainer 7c, and the outer diameter surface of the retainer 7c Lubrication performance between the inner ring surface of the outer ring and the guide surfaces can be more easily ensured. Therefore, the torque characteristics and the temperature rise characteristics can be further improved as compared with the case of the above-described first example. Note that this example and the above-described second example can be combined. In this case, the ends of the through holes 20, 20 (see FIG. 3) are opened at the bottoms of the concave grooves 21, 21. Other configurations and operations are the same as those of the above-described first example, and thus redundant description will be omitted.

Next, FIG. 5 shows a fourth example of the embodiment of the present invention, which is also described in the first aspect. Also in the case of this example, similarly to the first example of the above-described embodiment, by making the outer diameter surface of the retainer 7d close to the inner diameter surface of the outer ring 3 (see FIG. 1), the retainer 7d is attached to the outer ring. It is rotatably supported by guidance. And in the case of this example, this cage 7
In the inner surface of each pocket 8a of d, the axial direction of the main portion 15 {vertical direction of FIG. 5B} {one side} {the upper surface of FIG. 5 (b)}
Then, the concave portion 22 is formed in the cylindrical concave portion 17a provided between the pair of elastic pieces 16 and 16, and the concave portion 17 is formed.
The retainer 7d is provided so as to be recessed radially outward from the cylindrical surface and to be continuous from the inner diameter surface to the outer diameter surface in the radial direction of the retainer 7d. The recess 22
Center of curvature of is to match the center of curvature of the concave portion 17a, the radius of curvature R ₂₂ of the recess 22, the concave portion 1
7a is slightly larger than the radius of curvature _R17a .

As described above, each pocket 8a has a recess 2
In the case of the present example in which 2 is provided, the grease easily spreads between the inner diameter surface of the outer ring 3 and the outer diameter surface of the retainer 7b (between the guide surfaces), and the lubrication performance is more easily improved. In addition, in the case of the present example, grease is easily spread between the inner surface of each pocket 8a and the rolling surface of each ball 6, and the spin friction generated between each pocket 8a and each ball 6 can be reduced. . For this reason, the torque characteristics and the temperature rise characteristics can be further improved as compared with the case of the above-described first example. Other configurations and operations are the same as those of the above-described first example, and thus redundant description will be omitted.

Next, FIG. 6 corresponds to claims 1-2.
15 shows a fifth example of the embodiment of the present invention. Also in the case of this example, similarly to the first example of the above-described embodiment, by making the outer diameter surface of the retainer 7a close to the inner diameter surface of the outer ring 3,
The retainer 7a is rotatably supported by the outer ring guide. In the case of this example, the center line α in the axial direction of the outer ring raceway 2 (and the inner ring raceway 4) is set more than the center line β in the axial direction of the outer ring 3 (and the inner ring 5). It is located on the tip side (left side in FIG. 6) of the elastic piece 16 to be constituted. In the case of such an example, the retainer 7
Since the axial dimension of the outer ring shoulder 19 on the side of the main portion 15 constituting the main portion 15a can be increased, the inner diameter surface of the outer ring shoulder 19 and the main portion 1
5, the axial dimension of each guide surface can be increased, and the rotational stability of the retainer 7a can be more easily secured. Also, compared to the case where the respective center lines α and β are matched,
The elastic piece 16 and the seal plate 1 facing the elastic piece 16
Since the distance to zero can be reduced, grease stagnating on the elastic piece 16 side can be scraped off by the elastic piece 16.
Therefore, the grease existing in the space 18 in which the balls 6 are installed can be effectively used, and the life of the grease can be extended. In the case of this example, the second embodiment of the above-described embodiment is used.
Although the lubrication supply passages such as the through holes 20, the concave grooves 21, and the concave portions 22 are not provided in the retainer 7a as shown in
If necessary, the main portion 15 and the pocket 8 of the retainer 7a
a (see FIG. 2). Other configurations and operations are the same as those of the above-described first example, and thus redundant description will be omitted.

[0030]

As described above, the ball bearing of the present invention is constructed and operates as described above. Therefore, even when the ball bearing is used in a high-speed rotation and high-temperature environment, the vibration of the cage increases and the grease deteriorates early. This can contribute to the realization of a rotary machine having excellent durability and reliability.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first example of an embodiment of the present invention.

FIGS. 2A and 2B are views showing a cage and a ball, and FIG.
The figure corresponding to A section, (b) is the arrow B view of (a).

FIG. 3 is a view similar to FIG. 2, showing a second example of the embodiment of the present invention;

FIG. 4 is a view similar to FIG. 2, showing the third example.

FIG. 5 is a view similar to FIG. 2, showing the fourth example.

FIG. 6 is a view similar to FIG. 1, showing the fifth example;

FIG. 7 is a sectional view showing a conventional structure.

8A and 8B are views showing a retainer and a ball, and FIG.
The figure corresponding to C section, (b) is the arrow D view of (a).

FIG. 9 is a perspective view showing only a retainer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1a Ball bearing 2 Outer raceway 3 Outer raceway 4 Inner raceway 5 Inner raceway 6 Ball 7, 7a, 7b, 7c, 7d Cage 8, 8a Pocket 9 Locking groove 10 Seal plate 11 Core metal 12 Elastic material 13 Seal lip 14 Seal Groove 15 Main part 16 Elastic piece 17, 17a Concave surface 18 Space 19 Outer ring shoulder 20 Through hole 21 Concave groove 22 Concave

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J101 AA02 AA32 AA42 AA52 AA62 BA25 BA44 BA50 BA53 BA54 BA55 EA03 EA04 EA06 EA31 EA34 EA41 FA01 FA32 GA16 GA24 GA29

Claims (2)

[Claims] An outer race having an outer raceway on an inner peripheral surface, an inner racer having an inner raceway on an outer peripheral surface, a plurality of balls rotatably provided between the outer raceway and the inner raceway, By holding a plurality of balls so that they can roll freely, by filling grease in the space where each of the balls is installed,
In a ball bearing for lubricating a rolling contact portion between the outer raceway and the inner raceway and each of the balls, the retainer is made of a heat-resistant synthetic resin, and has an annular main portion and an annular main portion. A plurality of elastic pieces provided on one surface in the axial direction of the portion, and by bringing the outer diameter surface of the cage closer to the inner diameter surface of the outer ring, the cage is guided by the outer ring. A ball bearing characterized by being rotatably supported. 2. The center of at least one of the outer raceway and the inner raceway in the axial direction is located closer to the distal end of the elastic piece constituting the retainer than the center of the raceway having the raceway in the axial direction. The ball bearing according to claim 1, wherein