JP2021143739A - Cage for angular ball bearing and angular ball bearing - Google Patents

Abstract

To obtain a cage for an angular ball bearing which can sufficiently secure a ball holding force, can suppress the damage of a large-diameter ring part, and can be suitably used in a hub unit bearing.SOLUTION: A cage 5 for an angular ball bearing comprises: circular small-diameter ring parts 10; circular large-diameter ring parts 11 arranged coaxial with the small-diameter ring parts 10, and larger than the small-diameter ring parts 10 in diameters; a plurality of column parts 12 arranged in a circumferential direction with equal intervals, and connecting the small-diameter ring parts 10 and the large-diameter ring parts 11; and a plurality of pockets 13 formed at a portion surrounded by the pair of column parts 12 which adjoin the small-diameter ring parts 10 and the large-diameter ring parts 11 in the circumferential direction, and holding balls 4. A slit 15 for making the large-diameter ring parts 11 discontinuous in the circumferential direction are formed in positions which coincide with centers of the pockets 13 with respect to the circumferential direction out of the large-diameter ring parts 11.SELECTED DRAWING: Figure 2

Description

The present invention relates to a cage for angular contact ball bearings and an angular contact ball bearing provided with a cage for angular contact ball bearings.

In a single-row angular contact ball bearing, for example, as described in Japanese Patent Application Laid-Open No. 2015-48874 (Patent Document 1), a plurality of balls are placed in the circumferential direction by using an inclined type angular contact ball bearing cage. They are arranged at equal intervals and each ball is held so that it can roll freely.

The tilted angular contact ball bearing cage has a substantially conical trapezoidal shape as a whole, and has an annular small-diameter ring portion, an annular large-diameter ring portion, and a small-diameter ring portion and a large-diameter ring portion. It is provided with a plurality of pillars to be connected, and a plurality of pockets surrounded on all sides by a small-diameter ring portion, a large-diameter ring portion, and a pair of pillar portions adjacent to each other in the circumferential direction.

On the other hand, hub unit bearings used for rotatably supporting wheels are rear combination type double row angular contact ball bearings that support moment load based on road surface reaction force, and are not only durable but also durable. High rigidity is required to improve the steering stability of the vehicle. Therefore, in the hub unit bearing, it is necessary to secure a long distance between rows of balls arranged in multiple rows. In view of such circumstances, as the hub unit bearing, for example, a crown-type cage for angular contact ball bearings as described in Japanese Patent Application Laid-Open No. 2014-169777 (Patent Document 2) is used.

The crown-shaped cage for angular contact ball bearings has a substantially conical trapezoidal shape as a whole, and has an annular rim portion and a plurality of pillar portions extending in the axial direction from multiple locations in the circumferential direction of the rim portion. And a plurality of pockets surrounded on three sides by a rim portion and a pair of pillar portions adjacent to each other in the circumferential direction. Since the crown-type angular contact ball bearing cage does not have the large-diameter ring portion of the inclined angular contact ball bearing cage, the axial dimensions can be shortened and the distance between rows of balls can be increased. It will be advantageous.

However, in the crown type angular contact ball bearing cage, each of the pillars has a cantilever structure, so compared to the inclined type angular contact ball bearing cage in which each of the pillars has a double-sided structure, the ball bearing Holding power tends to be low. In the hub unit bearing assembly process, a cage with balls inserted in the pocket is installed inside the outer ring track in the radial direction. Since the bearing is low, the ball is likely to fall out of the pocket during such assembling work.

In view of these circumstances, for example, U.S. Pat. No. 4,330,160 (Patent Document 3) states that the holding force of balls can be secured, and when applied to a hub unit bearing, rows of balls are arranged. The structure of a cage for inclined angular contact ball bearings capable of increasing the distance is disclosed. FIG. 7 shows a cage 100 for angular contact ball bearings having a conventional structure as described in US Pat. No. 4,330,160.

The angular contact ball bearing cage 100 includes an annular small diameter ring portion 101, an annular large diameter ring portion 102, a plurality of pillar portions 103, and a plurality of pockets 104. In particular, in the holder 100 for angular contact ball bearings having a conventional structure, the thickness of the large-diameter ring portion 102 in the axial direction is reduced, and the side surface of the large-diameter ring portion 102 facing the opposite side to the pocket 104 is pocketed. It is arranged at substantially the same axial position as the axial top of the ball 105 held in 104. As a result, the large-diameter ring portion 102 is prevented from protruding significantly from the ball 105 in the axial direction.

In the conventional structure angular contact ball bearing cage 100, the balls 105 can be arranged closer to a sealing device (not shown) by the amount that the thickness of the large-diameter ring portion 102 is reduced, and the distance between the rows of the balls can be increased. It can be lengthened. Further, the ends on both sides of the pillar portion 103 in the axial direction are connected to the small diameter ring portion 101 and the large diameter ring portion 102, respectively, so that the rigidity of the pillar portion 103 in the circumferential direction can be increased. Therefore, it is possible to secure the holding force of the ball 105 and prevent the ball 105 from falling off.

Japanese Unexamined Patent Publication No. 2015-48874 Japanese Unexamined Patent Publication No. 2014-169777 U.S. Pat. No. 4,330,160

However, since the large-diameter ring portion 102 of the cage 100 for an angular contact ball bearing having a conventional structure has a thin thickness, a misalignment occurs between the ball 105 and the pocket 104 when the ball 105 is inserted into the pocket 104. However, when a force is applied from the ball 105 to the peripheral portion of the pocket 104, the large-diameter ring portion 102 is likely to be damaged.

As described above, when an inclined structure having a large-diameter ring portion is adopted as a cage for angular contact ball bearings to be incorporated in a hub unit bearing in order to prevent the balls from falling off, the distance between rows of balls Due to the need to increase the distance, it is difficult to secure the thickness of the large-diameter ring portion, and the large-diameter ring portion is likely to be damaged when the ball is inserted into the pocket.

The present invention has been made to solve the above problems, and is capable of suppressing ball dropout and suppressing damage to a large-diameter ring portion, and is suitable for holding for angular contact ball bearings that can be used for hub unit bearings. The purpose is to provide a vessel.

As a result of diligent studies on means for solving the above-mentioned problems of the prior art, the inventors of the present invention paid attention to the deformation characteristics of the pillars constituting the cage for angular contact ball bearings. That is, in an angular contact ball bearing, as the diameter of the ball increases and the number of balls increases, the rated load increases and the life can be extended. Therefore, the cross-sectional shape of the column has a large radial dimension and a circumference. The shape has a small directional dimension. For this reason, the pillar portion has a deformation characteristic that it is easily deformed in the circumferential direction due to such a shape, but is difficult to be deformed in the radial direction. Therefore, even when a force in the radial direction is applied from the ball, the pillar portion is not easily deformed in the radial direction and is easily deformed in the circumferential direction. Therefore, the inventors of the present invention can utilize such deformation characteristics of the pillar portion to create a state in which the pillar portion is easily deformed in the circumferential direction and a state in which the pillar portion is difficult to be deformed in the circumferential direction. If possible, we came up with the idea that it would be possible to prevent the balls from falling off and prevent damage to the large-diameter ring. The present invention has been completed based on such findings. Specifically, the cage for angular contact ball bearings and the angular contact ball bearings of the present invention employ the following means.

The cage for angular contact ball bearings of the present invention includes an annular small-diameter ring portion, an annular large-diameter ring portion, a plurality of pillar portions, and a plurality of pockets.
The large-diameter ring portion is arranged coaxially with the small-diameter ring portion and has an outer diameter larger than that of the small-diameter ring portion.
The pillars are arranged at equal intervals in the circumferential direction, and are inclined outward in the radial direction as the distance from the small-diameter ring to the large-diameter ring in the axial direction. Connect with the part.
The pocket is for holding a ball, and is provided in a portion surrounded by the small-diameter ring portion, the large-diameter ring portion, and a pair of pillar portions adjacent to each other in the circumferential direction.
The large-diameter ring portion is provided with a slit that discontinues the large-diameter ring portion in the circumferential direction at a position that coincides with the center of the pocket (central portion in the circumferential direction) in the circumferential direction.
In other words, the large-diameter ring portion is provided with a slit at a position where it overlaps with the pocket in the axial direction so as to discontinue the large-diameter ring portion in the circumferential direction.

The angular contact ball bearing of the present invention is arranged between an outer ring member having an angular outer ring track on the inner peripheral surface, an inner ring member having an angular inner ring track on the outer peripheral surface, and the outer ring track and the inner ring track. A plurality of balls and a cage for holding the balls in a rollable manner are provided, and the cage is a cage for angular contact ball bearings according to an aspect of the present invention.

The angular contact ball bearing according to one aspect of the present invention can be used as a hub unit bearing for rotatably supporting a wheel of an automobile with respect to a suspension device.

According to the present invention, the slit provided in the large-diameter ring portion can create a state in which the pillar portion is easily deformed in the circumferential direction and a state in which the pillar portion is difficult to be deformed in the circumferential direction. Therefore, it is possible to realize a cage for angular contact ball bearings that can be suitably used for hub unit bearings, which can suppress the falling of balls and the damage of the large diameter ring portion.

FIG. 1 is a cross-sectional view of a hub unit bearing according to the first example of the embodiment. FIG. 2 is a cross-sectional view showing a cage for angular contact ball bearings in the right row taken out from the hub unit bearing of FIG. FIG. 3 is a side view of the cage for angular contact ball bearings according to the first example of the embodiment as viewed from the left side of FIG. 4A and 4B are enlarged views of a portion corresponding to the part A in FIG. 3, where FIG. 4A shows a state in which a slit gap exists, and FIG. 4B shows a state in which the slit gap disappears. FIG. 5 is a schematic view seen from the large-diameter ring portion side in the axial direction, which is shown for explaining the first step of the assembly process of the hub unit bearing. FIG. 6 is a schematic view shown for explaining the second step of the assembly process of the hub unit bearing. FIG. 7 is a half cross-sectional view showing a cage for angular contact ball bearings having a conventional structure.

[First Example of Embodiment]
A first example of the embodiment will be described with reference to FIGS. 1 to 6.

In this example, the angular contact ball bearing provided with the angular contact ball bearing cage of the present invention is applied to a hub unit bearing (double row angular contact ball bearing) for rotatably supporting the wheels of an automobile with respect to a suspension device. This case will be described.

[Overall configuration of hub unit bearing]
The hub unit bearing 1 of this example is a so-called first-generation hub unit bearing, and has one outer ring 2 corresponding to an outer ring member and a pair (two) inner rings 3 corresponding to an inner ring member. , A plurality of balls 4 and two angular ball bearing cages 5 are provided.

The outer ring 2 has a double-row outer ring track 6 on the inner peripheral surface, each of which is an angular type. Each of the pair of inner rings 3 has an angular inner ring track 7 on the outer peripheral surface. The pair of inner rings 3 are arranged coaxially with the outer ring 2 on the inner side in the radial direction of the outer ring 2 in a state where the end faces on the small diameter side are butted against each other. The inner ring orbits 7 of the pair of inner rings 3 are arranged in a double row at positions facing the outer ring orbits 6 in the double row in the radial direction. A plurality of balls 4 are arranged between the outer ring track 6 of the double row and the inner ring track 7 of the double row so as to be separated from each other in the circumferential direction, and the angular contact ball bearings of each row are provided. It is rotatably held by the cage 5. The balls 4 arranged in a plurality of rows are provided with a back surface combination type (DB type) contact angle.

When assembled to the vehicle, the outer ring 2 is internally fitted and fixed to a knuckle constituting a suspension device (not shown). On the other hand, the pair of inner rings 3 are externally fitted and fixed to a hub ring (not shown) having a hub flange for supporting the wheel. Therefore, in the hub unit bearing 1 of this example, the outer ring 2 is a stationary ring that does not rotate even during use, and the pair of inner rings 3 is a rotating wheel that rotates during use.

Each of the openings on both sides in the axial direction of the internal space 8 existing between the inner peripheral surface of the outer ring 2 and the outer peripheral surface of the pair of inner rings 3 is closed by a combination seal ring 9 which is a sealing device. The combined seal ring 9 prevents the grease sealed in the internal space 8 from leaking to the external space through the openings on both sides in the axial direction of the internal space 8, and also prevents muddy water existing in the external space from leaking to the external space. Foreign matter is prevented from entering the internal space 8 through the openings on both sides in the axial direction of the internal space 8.

Next, the cage 5 for angular contact ball bearings of this example will be described with reference to FIGS. 2 to 4.
Regarding the cage 5 for angular contact ball bearings, the axial direction, the radial direction, and the circumferential direction refer to each direction relating to the small diameter ring portion 10 described later, which constitutes the cage 5 for angular contact ball bearings, unless otherwise specified. Further, since the two angular contact ball bearing cages 5 incorporated in the hub unit bearing 1 are assembled in opposite directions with respect to the axial direction, the angular contact ball bearing cage 5 in the right column of FIG. 1 and the cage 5 shown in FIG. The direction with respect to the axial direction is opposite to that of the cage 5 for angular contact ball bearings in the left column of 1. Specifically, regarding the cage 5 for angular contact ball bearings in the right column of FIG. 1, the right side is referred to as one side in the axial direction and the left side is referred to as the other side in the axial direction. With respect to 5, the left side is referred to as one side in the axial direction, and the right side is referred to as the other side in the axial direction.

[Overall configuration of cage for angular contact ball bearings]
The angular contact ball bearing cage 5 is an inclined type angular contact ball bearing cage that is integrally manufactured by injection molding (axial draw molding) of synthetic resin, and has a substantially conical trapezoidal shape as a whole. doing.

Examples of the synthetic resin constituting the cage 5 for angular ball bearings include polyamide 6 (PA66), polyamide 6 (PA6), polyamide 46 (PA46), polyamide 9T (PA9T), polyphenylene sulfide (PPS), and polyethylene terephthalate (PPS). Various synthetic resins such as PET), polyacetal (POM), and phenolic resin (PF) can be adopted. Various reinforcing fibers such as glass fiber, polyethylene fiber, carbon fiber, and aramid fiber can be mixed with these synthetic resins, if necessary.

The cage 5 for angular contact ball bearings includes an annular small-diameter ring portion 10, an annular large-diameter ring portion 11, a plurality of columnar portions 12 each having a columnar shape, and a plurality of pockets for holding the ball 4. 13 and.

The small-diameter ring portion 10 and the large-diameter ring portion 11 are separated from each other in the axial direction and are arranged coaxially with each other. The plurality of pillar portions 12 are arranged at equal intervals in the circumferential direction, and the small-diameter ring portion 10 and the large-diameter ring portion 11 are connected in the axial direction. The pocket 13 is formed (defined) in a portion surrounded on all sides by a small-diameter ring portion 10, a large-diameter ring portion 11, and a pair of pillar portions 12 adjacent to each other in the circumferential direction.

The cage 5 for angular contact ball bearings of this example is manufactured by injection molding by axial draw using a pair of molding molds (fixed mold and mobile mold) (not shown). Therefore, at the boundary between the radial outer portion and the radial inner portion of the inner surface of the pocket 13, a parting line 14 located at the abutting portion between the pair of molding dies at the time of injection molding exists. The parting line 14 extends axially along the inner surface of the pocket 13 from the outer peripheral edge of the small-diameter ring portion 10 to the inner peripheral edge of the axially one-sided end of the pillar portion 12 and faces one axial direction. It is slightly inclined outward in the radial direction.

<Small diameter ring part>
The small-diameter ring portion 10 is formed in an annular shape as a whole, and is continuous over the entire circumference. The small-diameter ring portion 10 is arranged radially inside _{the center O 4 of the} ball 4 (= the center O _{13 of the pocket 13).} The outer peripheral surface of the small-diameter ring portion 10 is a tapered surface whose outer diameter increases toward one side in the axial direction. The inner peripheral surface of the small-diameter ring portion 10 is a cylindrical surface whose inner diameter does not change in the axial direction. The other axial side of the small-diameter ring portion 10 is a flat surface disposed on a virtual plane perpendicular to the central axis O ₅ of the angular contact ball bearing cage 5. One side surface of the small diameter ring portion 10 in the axial direction is a concave curved surface having a radius of curvature slightly larger than the radius of curvature of the ball 4, and constitutes a radial inner portion of the inner surface of the pocket 13.

<Large diameter ring>
The large-diameter ring portion 11 is formed in an annular shape as a whole, but unlike the small-diameter ring portion 10, it is not continuous over the entire circumference. The large-diameter ring portion 11 has slits 15 which are discontinuous portions at a plurality of locations in the circumferential direction, and is configured to be discontinuous in the circumferential direction. Large-diameter portion 11 is located radially outwardly of the center O ₄ of the ball 4. Therefore, the large-diameter ring portion 11 has an outer diameter and an inner diameter larger than the outer diameter of the small-diameter ring portion 10. The outer peripheral surface of the large-diameter ring portion 11 is a cylindrical surface whose outer diameter does not change in the axial direction. One axial side surface of the large-diameter portion 11 is a flat surface disposed on a virtual plane perpendicular to the central axis O ₅ of the angular contact ball bearing cage 5. The other side surface in the axial direction of the large-diameter ring portion 11 is a concave curved surface having a radius of curvature slightly larger than the radius of curvature of the ball 4, and constitutes a radial outer portion of the inner surface of the pocket 13.

"slit"
The slit 15 is a cut (micro gap) having a small circumferential width extending in the radial direction, and penetrates the large-diameter ring portion 11 in the radial direction and the axial direction, respectively. The slit 15 is provided at a position of the large-diameter ring portion 11 that matches the pocket 13 in the circumferential direction, and the large-diameter ring portion 11 is not provided in the circumferential direction at the portion provided with the slit 15. It is continuous. In other words, the slit 15 is provided at a position where it overlaps with the pocket 13 in the axial direction (a position deviated from the pillar portion 12 in the circumferential direction). In particular, in this example, the slit 15 is provided at a position in the large-diameter ring portion 11 that coincides with the center O ₁₃ (the central portion in the circumferential direction of the pocket 13) of all the pockets 13 in the circumferential direction. There is. Therefore, the slits 15 are arranged at equal intervals in the circumferential direction and are provided in the same number as the pockets 13. When the arcuate portion of the large-diameter ring portion 11 connecting the pillar portions 12 adjacent to each other in the circumferential direction is called a connecting portion, the slit 15 is provided at the central portion in the circumferential direction of the connecting portion. It can also be expressed as. Since the other side surface of the large-diameter ring portion 11 in the axial direction is a concave curved surface, the slit 15 is formed in the portion of the large-diameter ring portion 11 having the thinnest axial thickness.

Since the slits 15 are formed at positions of the large-diameter ring portion 11 that match each of the pockets 13 in the circumferential direction, each of the pillar portions 12 is easily deformed in the circumferential direction. That is, since each of the column portions 12 has a cantilever structure similar to the crown type cage for angular contact ball bearings, it is easily deformed in the circumferential direction.

However, the pillar portion 12 does not remain in a state of being easily deformed in the circumferential direction, but is also switched to a state of being difficult to be deformed in the circumferential direction. The deformation of the pillar portion 12 in the circumferential direction is within the range of the circumferential width (slit width) of the slit 15, and as shown in FIG. 4A, there is a gap in the slit 15. Then, the pillar portion 12 is in a state of being easily deformed in the circumferential direction. On the other hand, when the deformation of the pillar portion 12 in the circumferential direction becomes equal to or larger than the circumferential width of the slit 15, and the gap of the slit 15 disappears as shown in FIG. 4B, the pillar portion 12 Since the deformation is suppressed by the pillars 12 adjacent to each other in the circumferential direction, the pillars 12 are less likely to be deformed in the circumferential direction.

As described above, the ease of deformation of the pillar portion 12 in the circumferential direction changes depending on the presence or absence of a gap in the slit 15, so that the size of the circumferential width H of the slit 15 is appropriately regulated.
Specifically, when the circumferential width H of the slit 15 is inserted into the pocket 13 one by one in the first step of the assembly process of the hub unit bearing 1 described later, the circumferential direction of the pocket 13 The gap of the slit 15 does not disappear (the width H in the circumferential direction does not become zero) by the degree of deformation that occurs in the pair of pillars 12 existing on both sides, and the hub unit bearing 1 to be described later is assembled. In the second step of the process, when all the column portions 12 are deformed until the diameter of the circumscribed circle of the ball 4 becomes equal to or less than the inner diameter of the small shoulder portion 22 of the outer ring 2, the slit without restraining the ball 4 The size is such that the gaps of 15 disappear (the width H in the circumferential direction becomes zero). The circumferential width H of the slit 15 varies depending on the type of synthetic resin constituting the angular contact ball bearing cage 5, the size of the angular contact ball bearing cage 5, the number of pockets 13, and the like, but is 0.15 mm. It is about 0.25 mm, and is about 1.1% to 2.4% of the diameter D of the ball 4. Such a slit 15 can be formed during injection molding by axial draw, or can be formed by cutting with a tool such as a cutter after injection molding. In this example, the circumferential width H of all the slits 15 provided in the large-diameter ring portion 11 is the same, but the circumferential width of the slit 15 is set in consideration of the insertion order of the balls 4. It can also be different from each other.

<< Meat removal part >>
One side surface of the large-diameter ring portion 11 in the axial direction is arranged on the other side in the axial direction with respect to the axial top portion T (see FIG. 2) of the ball 4 held in the pocket 13. In other words, the axial top portion T of the ball 4 is arranged so as to project axially from one side surface of the large-diameter ring portion 11 in the axial direction. Therefore, in the large-diameter ring portion 11, the radial outer side is convex toward the radial inner part of _{the portion provided with the slit 15 (the position that coincides with the center O 13 of the pocket 13 with respect to the circumferential direction).} A bow-shaped thinning portion (notch) 16 is provided. Then, the end portion (including the top portion T) on one side in the axial direction of the ball 4 is projected in the axial direction through the thinning portion 16. In this example, since the end portion of the ball 4 on one side in the axial direction can be projected to one side in the axial direction from the one side surface in the axial direction of the large-diameter ring portion 11 through the thinning portion 16, the ball 4 Can be arranged close to the seal ring 9, and the inter-row distance L (see FIG. 1) between the balls 4 arranged in the plurality of rows can be lengthened.

<Pillar>
The pillar portion 12 is inclined in the radial outward direction as it approaches the large-diameter ring portion 11 from the small-diameter ring portion 10 in the axial direction (toward one side in the axial direction). Of the outer peripheral surface of the column portion 12, the other half portion in the axial direction is a tapered surface whose outer diameter increases toward one side in the axial direction, and the one half portion in the axial direction has the same outer diameter as the large diameter ring portion 11. It is a cylindrical surface that has and does not change its outer diameter in the axial direction. The inner peripheral surface of the pillar portion 12 is a tapered surface whose outer diameter increases toward one side in the axial direction. Therefore, the thickness of the pillar portion 12 in the radial direction is a portion located radially outside the parting line 14, and becomes thinner toward the other side in the axial direction, and is located radially inside the parting line 14. It becomes thinner toward one side in the axial direction. The pillar portion 12 has a cross-sectional shape having a large radial dimension and a small circumferential dimension. Therefore, the pillar portion 12 has a deformation characteristic that it is easily deformed in the circumferential direction but difficult to be deformed in the radial direction.

Of the circumferential side surfaces of the pillar portion 12, the portion located radially outside the parting line 14 is a concave curved surface having a radius of curvature slightly larger than the radius of curvature of the ball 4 on one side in the axial direction. The other side in the axial direction is a cylindrical concave surface. Further, of the circumferential side surface of the pillar portion 12, the portion located radially inside the parting line 14 has a cylindrical concave surface on one side in the axial direction and a ball 4 on the other side in the axial direction. It is a concave curved surface having a radius of curvature slightly larger than the radius of curvature of.

<pocket>
Each of the plurality of pockets 13 is formed by an axial one side surface of the small diameter ring portion 10, an axial other side surface of the large diameter ring portion 11, and a circumferential side surface of a pair of pillar portions 12 adjacent to each other in the circumferential direction. It is formed (painted) in the area surrounded on all sides. Of the inner surface of the pocket 13, a portion located radially outside the parting line 14 is composed of an axially other side surface of the large-diameter ring portion 11 and a radial outer portion of the circumferential side surface of the pillar portion 12. ing. Of the inner surface of the pocket 13, the portion located radially inside the parting line 14 is composed of one axial side surface of the small diameter ring portion 10 and the radial inner portion of the circumferential side surface of the pillar portion 12. There is. The radial inner opening of the pocket 13 is smaller than the diameter of the ball 4. In other words, with the ball 4 inserted in the pocket 13, it is possible to prevent the ball 4 from falling inward in the radial direction between the ball 4 and the opening inside the pocket 13 in the radial direction. , The clerk fee (so-called snapping fee) is provided. In particular, in this example, even in a state where the column portion 12 is deformed in the circumferential direction and the gap of the slit 15 disappears, the opening on the radial inside of the adjacent pocket 13 does not become larger than the diameter of the ball 4. The size of the clerk is set in.

[Assembly process of hub unit bearing]
The assembly process of the hub unit bearing 1 of this example will be described with reference to FIGS. 5 and 6.
When assembling the hub unit bearing 1, as a first step, the balls 4 are inserted into each of the pockets 13 constituting the angular ball bearing cage 5, and an intermediate assembly (ball holder set) 17 is obtained. Next, as a second step, each of the two intermediate assemblies 17 is incorporated into the radial inside of the double-row outer ring track 6 from one side in the axial direction. Then, as a third step, the inner ring 3 is inserted inside the intermediate assembly 17 in the radial direction to obtain the hub unit bearing 1.

In particular, when the first step is performed, a ball 4 constant distribution device (not shown) and a pushing surface 18 for pushing the balls 4 are provided, which rotate along the inner peripheral surface of the angular contact ball bearing cage 5. The rotating jig 19 to be used is used. First, the ball 4 supplied from the regular distribution device is placed on the radial inner opening of the pocket 13 (see the ball 4 in the center of FIG. 5). Then, as shown by an arrow in FIG. 5, the rotating jig 19 is rotated around the central axis O ₅ of the angular ball bearing cage 5, so that the ball 4 is tilted from the circumferential direction. Press toward the outside in the radial direction, and push the ball 4 into the inside of the pocket 13 through the opening on the inside in the radial direction (see the second ball 4 from the left end in FIG. 5). As a result, the ball 4 is inserted into the pocket 13 (see the leftmost ball 4 in FIG. 5). In this way, all the balls 4 are inserted into the pockets 13 in order in the circumferential direction to obtain the intermediate assembly 17 as shown in FIG.

When performing the second step, as shown in FIG. 6, a guide jig 21 having a guide surface 20 inclined in a direction in which the inner diameter becomes smaller as it approaches the outer ring track 6 in the axial direction is used. With the end of the guide jig 21 on the other side in the axial direction inserted inside the outer ring 2, the intermediate assembly 17 is passed through the inside of the guide jig 21 in the radial direction toward the other side in the axial direction. .. As a result, the ball 4 constituting the intermediate assembly 17 is pressed inward in the radial direction by the guide surface 20, and the circumscribed circle diameter of the ball 4 is set adjacent to one side of the outer ring track 6 in the axial direction. Make it smaller than the inner diameter of. The diameter of the circumscribed circle of the ball 4 constituting the intermediate assembly 17 increases when it passes through the guide jig 21, and becomes larger than the inner diameter of the small shoulder portion 22. Therefore, the balls 4 constituting the intermediate assembly 17 are locked to the small shoulder portion 22, and the intermediate assembly 17 is arranged radially inside the outer ring track 6.

According to the cage 5 for angular contact ball bearings of this example as described above, damage to the large-diameter ring portion 11 can be suppressed, and the ball 4 can be suppressed from falling off.

That is, the cage 5 for angular contact ball bearings of this example has slits 15 at a plurality of positions of the large-diameter ring portion 11 so that each of the pillar portions 12 has a cantilever structure. Here, the pillar portion 12 has a deformation characteristic that is more easily deformed in the circumferential direction than in the radial direction due to its shape (cross-sectional shape). Therefore, the pillar portion 12 having a cantilever structure due to the slit 15 is easily deformed in the circumferential direction. Therefore, even if the misalignment between the balls 4 and the pockets 13 becomes large when the balls 4 are inserted into the pockets 13 one by one in the first step of the above-mentioned assembly process of the hub unit bearing 1. As long as the gap of the slit 15 does not disappear (the width H in the circumferential direction does not become zero), the force acting on the column portion 12 from the ball 4 is used to prevent the column portion 12 from being deformed in the radial direction. It can be easily deformed in the circumferential direction. Therefore, in this example, the tolerance for misalignment between the ball 4 and the pocket 13 can be increased. Further, when the pillar portion 12 is deformed in the circumferential direction, no force is applied to the large-diameter ring portion 11, so that the large-diameter ring portion 11 is damaged when the ball 4 is inserted into the pocket 13. Can be suppressed.

When the balls 4 are sequentially inserted into the pocket 13 in the circumferential direction as in the first step described above, the balls 4 inserted into the pocket 13 are deformed in the circumferential direction of the pillar portion 12. It comes to suppress. Therefore, when the last ball 4 is inserted into the pocket 13, the pillars 12 located on both sides of the pocket 13 in the circumferential direction are not easily deformed by the ball 4 in the circumferential direction. Therefore, when the misalignment between the ball 4 and the pocket 13 becomes large, the pillar portion is provided in a structure having no slit in the large-diameter ring portion, such as the conventional structure holder 100 for angular contact ball bearings (see FIG. 7). Due to insufficient deformation in the circumferential direction and the application of force to the peripheral part of the pocket, the cage (particularly the large-diameter ring part) is liable to be damaged. On the other hand, in this example, by providing the large-diameter ring portion 11 with the slit 15, the pillar portion 12 can be sufficiently deformed in the circumferential direction as long as the gap between the slits 15 does not disappear. Therefore, when the last ball 4 is inserted into the pocket 13, even if the misalignment between the ball 4 and the pocket 13 becomes large, the ball 4 is pocketed without damaging the large diameter ring portion 11. It becomes possible to insert it in 13.

Further, the cage 5 for angular contact ball bearings of this example is an inclined type angular contact ball bearing cage provided with a large diameter ring portion 11, but the large diameter ring portion 11 is provided with a plurality of slits 15 and is large. The diameter ring portion 11 is discontinuously configured in the circumferential direction. Therefore, each of the pillar portions 12 has a cantilever structure, and the holding force of the balls 4 tends to be low as it is, as in the case of a crown-type cage for angular contact ball bearings. Further, in the second step of the hub unit bearing assembly process described above, when the diameter of the circumscribed circle of the balls 4 constituting the intermediate assembly 17 is reduced to less than the inner diameter of the small shoulder portion 22, each of the pillar portions 12 is used. Is pressed in the circumferential direction by the ball 4 and deforms in the circumferential direction. Therefore, the opening on the inner side in the radial direction of the pocket 13 tends to expand, and the ball 4 easily falls off from the pocket 13. However, in this example, when each of the pillar portions 12 is deformed in the circumferential direction until the diameter of the circumscribed circle of the ball 4 becomes equal to or less than the inner diameter of the small shoulder portion 22, the gap of the slit 15 disappears (circumferential direction). The width H becomes zero). When the gap of the slit 15 disappears, the large-diameter ring portion 11 becomes continuous in the circumferential direction, and the deformation of the pillar portion 12 in the circumferential direction is arranged adjacent to the pillar portion 12 in the circumferential direction. The pillar portion 12 will be suppressed. Therefore, in this example, it is possible to prevent the ball 4 from falling out of the pocket 13 in the second step of the assembly step of the hub unit bearing 1.

As described above, according to the angular contact ball bearing cage 5 of this example, the pillar portion 12 can be deformed in the circumferential direction like the crown type angular contact ball bearing cage 5, and the pocket 13 Like a cage for inclined angular contact ball bearings, which can prevent damage to the large-diameter ring portion 11 when the ball 4 is inserted into the ball 4 and has a large-diameter ring portion continuous in the circumferential direction. , It is possible to prevent the ball 4 from falling out of the pocket 13 when the intermediate assembly 17 is assembled inside the outer ring track 6 in the radial direction.

When carrying out the present invention, the slits may be provided at positions that align with each of the pockets in the circumferential direction, or the slits may be provided intermittently with respect to the pockets (positions that align with every other pocket). Alternatively, it can be provided at a position that matches every other pocket. If a configuration in which slits are provided intermittently with respect to the pocket is adopted, the ball to be inserted last may be inserted into the pocket provided with the slit in the first step of the hub unit bearing assembly process. The ball can be inserted into the pocket without damaging the large-diameter ring portion. Further, when carrying out the present invention, it is possible to omit the thinning portion for projecting a part of the ball in the axial direction from the large-diameter ring portion.

The angular contact ball bearing of the present invention is not limited to the first generation hub unit bearing, but is applied to other generation hub unit bearings such as the second generation hub unit bearing and the third generation hub unit bearing. You can also. Further, the angular contact ball bearings of the present invention can be applied not only to hub unit bearings but also to single-row or double-row angular contact ball bearings incorporated in various mechanical devices.

1 Hub unit bearing 2 Outer ring 3 Inner ring 4 Ball 5 Angular contact ball Bearing cage 6 Outer ring orbit 7 Inner ring orbit 8 Internal space 9 Combination seal ring 10 Small diameter ring 11 Large diameter ring 12 Pillar 13 Pocket 14 Parting line 15 Slit 16 Thinning part 17 Intermediate assembly 18 Pushing surface 19 Rotating jig 20 Guide surface 21 Guide jig 22 Small shoulder part 100 Angular contact ball bearing cage 101 Small diameter ring part 102 Large diameter ring part 103 Pillar part 104 Pocket 105 Ball

Claims (3)

An annular small diameter ring and
An annular large-diameter ring portion that is arranged coaxially with the small-diameter ring portion and has an outer diameter larger than that of the small-diameter ring portion.
They are arranged at equal intervals in the circumferential direction, and incline toward the outer side in the radial direction toward the large-diameter ring portion from the small-diameter ring portion in the axial direction, and connect the small-diameter ring portion and the large-diameter ring portion. , Multiple pillars,
A plurality of pockets provided in a portion surrounded by the small-diameter ring portion, the large-diameter ring portion, and a pair of the pillar portions adjacent to each other in the circumferential direction, each of which holds a ball.
The large-diameter ring portion is provided with a slit at a position consistent with the center of the pocket in the circumferential direction to discontinue the large-diameter ring portion in the circumferential direction.
Cage for angular contact ball bearings. An outer ring member having an angular outer ring track on the inner peripheral surface,
An inner ring member having an angular inner ring track on the outer peripheral surface,
A plurality of balls arranged between the outer ring track and the inner ring track,
A cage for holding the ball in a rollable manner is provided.
The cage is the cage for angular contact ball bearings according to claim 1.
Angular contact ball bearings. The angular contact ball bearing according to claim 2, which is used as a hub unit bearing for rotatably supporting an automobile wheel with respect to a suspension device.

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