JP3571490B2 - Double row angular contact ball bearing - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a double-row angular contact ball bearing, and more particularly, to a double-row angular contact ball bearing in which a shoulder protruding radially inward is formed at one axial end portion and a central portion of an inner peripheral surface of an outer race.
[0002]
[Prior art]
Conventionally, as this type of double-row angular contact ball bearing, as shown in FIG. 4, there is one used to rotatably support a hub for mounting wheels on an axle. The double-row angular contact ball bearing has a generally cylindrical outer ring 1 functioning as a hub main body having a wheel mounting flange 11 extending radially outward on an outer peripheral surface, and 2 provided coaxially with the outer ring 1. It comprises two inner rings 2.3, a plurality of rows of balls B, and two retainers R1 and R2 for holding these rows of balls B. The double-row balls B are respectively arc-shaped orbits 21 and 31 formed on the outer peripheral surface of each inner ring 2.3 and are opposed to these orbits 21 and 31 obliquely to the radial direction. The outer race 1 is disposed between two raceway surfaces 13 and 14 formed on the inner peripheral surface of the vehicle body side cylindrical portion 1a with the shoulder 12 therebetween.
[0003]
[Problems to be solved by the invention]
The two cages R1 and R2 used in the double row angular contact ball bearing are different in size and shape from each other for the convenience of the currently employed bearing assembly process. Generally, in order to incorporate the ball, the retainer, and the inner ring into the outer ring, it is necessary to fit the ball into the pocket of the retainer, and assemble the ball around the orbit of the inner ring in a subassembly in which the ball is assembled to the retainer. For this reason, it is convenient to increase the outer diameter of the retainer so that the ball does not fall out of the pocket of the retainer. For this reason, conventionally, as shown in FIG. 4, the outer diameter of the retainer R2 on the vehicle body side (right side in the figure) is larger than the inner diameter of the wheel-side cylindrical portion 1b and the shoulder portion 12. Have been. Then, the ball B, the retainer R2, and the inner ring 3 are assembled in the outer ring 1 from the right to the left in the drawing as shown by an arrow a in a subassembly state.
[0004]
However, if the ball B on the wheel side (left side in the drawing), the retainer R1, and the inner ring 2 are also pushed in the direction of arrow a in the sub-assembly state, the shoulder is located at the center of the inner peripheral surface of the outer ring. Due to the presence of the part 12, it cannot be pushed further. Further, if it is attempted to assemble from left to right in the figure as shown by the arrow b, the sub-assembly cannot be inserted into the outer race 1 because of the presence of the shoulder 15 formed by the wheel-side cylindrical portion 1b. Further, as long as the retainer R1 has the same outer diameter as the retainer R2, the retainer R1 itself cannot be inserted due to the presence of the shoulders 12 and 15. Therefore, the outer dimension of the retainer R1 on the wheel side (left side in the figure) is formed smaller than the inner diameter of the shoulder portion 15 constituted by the wheel-side cylindrical portion 1b. After that, the ball B is pushed into each pocket of the retainer R1, and then the inner ring 2 is further pushed in the axial direction shown by the arrow b to assemble.
[0005]
As described above, conventionally, two types of large and small cages R1 and R2 are used for one bearing for the convenience of the bearing assembly process. Therefore, it is necessary to prepare two types of molds for manufacturing the cage. Yes, it causes cost increase.
[0006]
Accordingly, an object of the present invention is a double-row angular ball bearing of a type in which an outer ring has a shoulder protruding radially inward at one end portion and a central portion in an axial direction of an inner peripheral surface, and a common cage is provided. It is an object of the present invention to provide a double-row angular contact ball bearing which can be assembled by the above-described conventional bearing assembly method while being used.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the double-row angular contact ball bearing according to claim 1 has first and second shoulder portions projecting radially inward at one axial end portion and a central portion of the inner peripheral surface. An outer ring having raceways formed on both sides in the axial direction of the second shoulder; two inner races having raceways formed on respective outer peripheral surfaces thereof respectively opposed to the raceways of the outer race; and a raceway of the outer race. comprising a ball double row disposed between the two inner ring raceway, and two retainers of the same shape to hold at a certain distance a ball of each row in the circumferential direction, the second The ball, the retainer, and the inner ring, which are arranged on the side of the shoulder of the opposite side to the first shoulder, are arranged in a sub-assembly in the double-row angular ball bearing incorporated in the outer ring. The retainer has an inlet that opens axially outward and A body ball housing portion is formed at a predetermined interval in the circumferential direction through the, flexible and radially from an outer peripheral portion of the body in the inlet and the opposite side in the axial direction of each ball receiving part It is characterized in that it has a projection for preventing the ball from falling out in the radial direction outside the center of the ball toward the outside and preventing the ball from falling out in the radial direction. I have.
[0008]
In the double row angular contact ball bearing according to claim 1 , the tip is directed radially outward from the outer peripheral portion of the retainer body, which is located on the side opposite to the entrance of each ball storage portion in the axial direction, so that the tip is located radially outward from the center of the ball. Since the protrusion for preventing ball dropout is formed so as to be positioned, even if the outer diameter of the retainer body itself is not large enough to prevent ball dropout (radial outward dropout) , the above-mentioned protrusion is formed. The ball does not fall out of the ball storage portion even outside the outer ring by the action of. The incorporation of the ball into the raceway that will be located between the first shoulder and the second shoulder of the two raceways of the outer ring first requires only the retainer to be mounted on the first shoulder. From the end of the outer ring with the part, beyond the first shoulder, it is assembled into a predetermined position in the outer ring, and subsequently, a ball is inserted into each ball storage portion of the retainer. Thereafter, the inner ring is assembled. On the other hand, the incorporation of the ball into the raceway of the outer ring opposite to the first shoulder is performed in a subassembly state in which the ball is assembled to the cage around the raceway of the inner race, and the outer race without the shoulder is provided. Assembled from the end. As described above, the double-row angular contact ball bearing according to the first aspect is assembled according to the conventionally adopted assembly method.
[0009]
Further, in the double row angular contact ball bearing of the first aspect, unlike the conventional case, the same two cages are used, so that two types of metal cages were conventionally required. Since only one type of mold is required and a cage having a large size of the retainer body is not used as in the related art, the amount of material used is reduced, and the material cost is reduced accordingly.
[0010]
The double row angular contact ball bearing may be of a type in which an outer ring rotates or a type in which an inner ring rotates.
[0011]
The double row angular contact ball bearing according to claim 1 is further characterized in that the projection of the retainer has flexibility.
[0012]
The protrusion of the retainer has flexibility, so that when the retainer is inserted from the end of the outer ring with the first shoulder to a predetermined position in the outer ring, the outer diameter of the retainer at the tip of the protrusion Even if the dimension is larger than the inner diameter of the first shoulder, the retainer is pushed through the first shoulder by bending the protrusion to a predetermined position in the outer race.
[0013]
The double row angular contact ball bearing according to claim 2 is characterized in that the outer diameter of the retainer at the tip of the projection is smaller than the inner diameter of the second shoulder.
[0014]
The protrusion of each retainer is located at a position facing the second shoulder inside the outer ring, but the outer diameter of the retainer at the tip of the protrusion is smaller than the inner diameter of the second shoulder. The projection of the retainer does not contact the second shoulder of the outer race. Therefore, the outer diameter of the retainer at the tip of the projection is larger than the inner diameter of the second shoulder, and the resistance when the outer ring rotates is smaller than when the projection hits the second shoulder.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.
[0016]
FIG. 1 is a sectional view of a main part in the axial direction of an outer ring rotation type double row angular contact ball bearing for an axle according to an embodiment of the present invention. Reference numeral 5 denotes a wheel mounting flange 51 extending radially outward on an outer peripheral surface. The inner rings 6 and 7 are provided coaxially with the outer ring 5 inside a cylindrical portion (hereinafter referred to as a “body-side cylindrical portion”) 5 a of the outer ring 5 located closer to the vehicle body than the flange 51. It is.
[0017]
A shoulder portion (hereinafter, referred to as a central shoulder portion) 52 protruding radially inward is formed at a central portion of the inner peripheral surface of the vehicle body side cylindrical portion 5a of the outer ring 5. On the flange side, a cylindrical portion (hereinafter referred to as a wheel-side cylindrical portion) 5b into which a wheel (not shown) is fitted follows the vehicle-body-side cylindrical portion 5a. The inner peripheral surface of the wheel-side cylindrical portion 5b is located radially inward of the inner peripheral surface of the vehicle-body-side cylindrical portion 5a, and as a result, another shoulder ( Hereinafter, a side shoulder portion 53 is configured.
[0018]
Two arc-shaped tracks 54 and 55 are formed on both sides of the central shoulder 52 in the axial direction. Further, on the outer peripheral surface of each of the inner rings 6 and 7, arc-shaped orbits 61 and 71 are formed so as to face the respective orbits 54 and 55 of the outer ring 5 obliquely with respect to the radial direction. A plurality of balls B held by two retainers 8, 8 are arranged in a double row between the tracks 54, 55 of the outer ring 5 and the tracks 61, 71 of the two inner rings 6, 7. Have been. Each of the inner rings 6 and 7 is formed with annular grooves 62 and 72 for guiding an annular projection 81 provided on the inner side in the radial direction of the retainer 8, and the annular projections 81 play in the annular grooves 62 and 72. It is fitted with.
[0019]
The two retainers 8, 8 are formed of a synthetic resin so as to have flexibility, and are formed in the same shape and the same size using the same mold. And it is installed between the inner rings 6 and 7 and the outer ring 5 so that it may become symmetrical with respect to the plane extended in the radial direction, that is, symmetrically. The dimensions of the main body of the cage 8 substantially correspond to the dimensions of the small cage R1 used in the conventional double row angular contact ball bearing shown in FIG. As described above, in the present embodiment, both the left and right retainers 8, 8 have a size corresponding to the conventional small retainer R1, and therefore, compared to the conventional case using the large and small retainers R1, R2. And the amount of material used is reduced, thus reducing material costs. Further, since two types of cages R1 and R2 are conventionally used for one bearing, it is necessary to prepare two types of dies for manufacturing the cage, but in the present embodiment, one type of cage is used. Only the mold needs to be prepared, and the mold cost can be reduced. For these reasons, the bearing of the present embodiment can be manufactured at a lower cost than before.
[0020]
As shown in FIG. 2, a plurality of pockets 82 as ball storage portions are formed at regular intervals in the circumferential direction in the main body 80 of each retainer 8. Each pocket 82 is formed by a concave surface having a shape substantially complementary to the spherical surface of the ball B. Each pocket 82 has an inlet 83 opened outward in the axial direction and penetrates the retainer body 80 in the radial direction. The ball gripping portions 84, 84 on both sides in the circumferential direction of the entrance of each pocket 82 are flexible, so that when the balls are put in, they open in the circumferential direction to allow the balls to be inserted.
[0021]
As shown in FIGS. 1 and 2, the outer periphery of the retainer main body 80 has a curved portion for preventing the ball dropout at the axially opposite side of the entrance 83 of each pocket 82, that is, at the central portion on the back side of the pocket. The projections or claws 85 are integrally formed radially outward. The tip of the claw 85 is located radially outside the center of the ball B in the pocket 82. The outer diameter of the retainer 8 at the tip of the claw 85 is larger than the inner diameter of the side shoulder 53 of the outer ring 5, but smaller than the inner diameter of the central shoulder 52. Therefore, the claw 85 does not contact the central shoulder 52 during the rotation of the outer ring 5, and the resistance when the outer ring 2 rotates is reduced.
[0022]
The incorporation of the ball into the track 54 on the left side, that is, on the wheel side, of the left and right tracks 54, 55 of the outer ring is performed as follows. First, only the retainer 8 is pushed in the direction of the arrow b from the end on the wheel side of the outer ring 5 to a position near the track 54 over the side shoulder 53. At this time, the claw 85 of the retainer 8 bends, so that the outer diameter of the retainer 8 at the tip of the claw 85 is larger than the inner diameter of the side shoulder 53 of the outer race 5, but the inside of the side shoulder 53 is formed. Can be inserted. Subsequently, the ball B is inserted into each pocket 85 of the cage 8 from the same wheel side end, and finally the inner ring 6 is pushed into the outer ring 5 from the wheel side end. On the other hand, the incorporation of the ball B into the track 55 on the right side in the figure is performed in a subassembly state in which the ball B is mounted on the retainer 8 around the track 71 of the inner ring 7. At this time, each ball B does not fall out of the pocket 82 by the function of the claw 85 provided on the outer peripheral portion of the retainer main body 80. Finally, a seal member 9 is attached between the inner ring 7 and the outer ring 5. Thus, the assembly of the double-row angular contact ball bearing shown in FIG. 1 is completed.
[0023]
The retainer 8 used in the outer ring rotation type double row angular contact ball bearing for axle can also be used in the inner ring rotation type double row angular contact ball bearing shown in FIG. That is, one type of cage can be commonly used for different types of double row angular contact ball bearings. In FIG. 3, reference numeral 5 'denotes an outer ring, and other members are represented by the same numbers as those used in FIGS. In the case of the double-row angular contact ball bearing of the inner ring rotation type shown in FIG.
[0024]
【The invention's effect】
As is apparent from the above description, in the double row angular contact ball bearing of the first aspect, the retainer has a tip located radially outside the center of the ball to prevent the ball from coming off in the radial direction. Since the projections for prevention are provided, the outer diameter of the retainer body can be made small so that it can be incorporated beyond the shoulder of the outer ring. Does not fall out of the cage pocket. Therefore, the double-row angular contact ball bearing of claim 1 can be assembled by using the same retainer and using the conventionally adopted assembling method. Since the same cage is used in this way, the number of molds for fabricating the cage, which conventionally required two types, can be reduced to one type. Since a cage having a large size is not used, the amount of material to be used is reduced, and the material cost can be reduced accordingly.
[0025]
Further , since the protrusion of the retainer has flexibility, the protrusion of the retainer is bent even if the outer diameter of the retainer at the tip of the protrusion is larger than the inner diameter of the first shoulder. Thereby, it can be pushed into a predetermined position in the outer race from the end of the outer race having the first shoulder.
[0026]
In the double row angular contact ball bearing according to claim 2 , since the outer diameter of the retainer at the tip of the projection is smaller than the inner diameter of the second shoulder of the outer ring, the projection of the retainer is provided on the second shoulder. Since there is no contact, the resistance when the outer ring rotates can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an outer ring rotation type double row angular contact ball bearing according to an embodiment of the present invention.
FIG. 2 is a partial perspective view of a retainer used for the double-row angular contact ball bearing of FIG. 1;
3 is a sectional view of an inner ring rotating type double row angular contact ball bearing using the cage shown in FIG. 2;
FIG. 4 is a cross-sectional view of a conventional double-row angular contact ball bearing.
[Explanation of symbols]
5, 5 '... outer ring, 6 ... inner ring, 7 ... inner ring, 8 ... retainer, 9 ... sealing material, 52, 53 ... shoulder, 54, 55 ... track, 61, 71 ... track, 82 ... pocket, 83 ... The entrance of the pocket, 85 ... nail, B ... ball.

Claims (2)

First and second shoulders protruding radially inward are provided at one axial end portion and a central portion of the inner peripheral surface, and tracks are formed on both axial sides of the second shoulder portion. Outer ring,
Two inner races each having a raceway formed on each outer peripheral surface thereof, the raceway facing each raceway of the outer race,
A double-row ball disposed between the raceway of the outer race and the raceway of the two inner races,
Two cages of the same shape for holding the balls of each row at a constant interval in the circumferential direction,
The ball, the retainer, and the inner ring, which are arranged on the side of the second shoulder opposite to the first shoulder, are arranged in a sub-assembly in the double-row angular ball bearing incorporated in the outer ring. ,
Each of the above retainers
A main body having an inlet opened toward the outside in the axial direction and ball storage portions penetrating in the radial direction at regular intervals in the circumferential direction,
It has flexibility and is formed so that the tip is located radially outward from the center of the ball toward the outside in the radial direction from the outer peripheral portion of the main body on the side opposite to the entrance of the ball storage portion in the axial direction. A double-row angular contact ball bearing, comprising: a projection for preventing the ball from coming off radially outward . 2. The double-row angular contact ball bearing according to claim 1, wherein an outer diameter of the retainer at a tip of the protrusion is smaller than an inner diameter of the second shoulder . 3.

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