JP6413337B2 - 4-point contact ball bearing - Google Patents

Description

  The present invention relates to a four-point contact ball bearing, and more particularly to a four-point contact ball bearing used for a drive unit of, for example, a hybrid vehicle or an electric vehicle.

  A four-point contact ball bearing is capable of supporting axial loads in both directions with a single bearing, and has a higher moment rigidity than a deep groove ball bearing, so it has been suitable as a grease lubricated ball bearing for engine accessories. Is used.

  In addition, since the four-point contact ball bearing has a total of four contact points on the outer inner ring and the ball, a rated load that is the same as that of the double-row bearing can be obtained by the size of the single-row bearing. In some cases, for example, it is used for supporting a gear load in a drive unit of a hybrid vehicle.

  When a four-point contact ball bearing is used for driving an automobile, its usage is the same as that of a deep groove ball bearing, so creep occurs between the outer ring and the housing (aluminum case) depending on the bearing specifications and usage conditions. there is a possibility.

  As a method for preventing creep of the four-point contact ball bearing, a fixing key is disposed between the inclined surface formed at one axial end of the outer peripheral surface of the outer ring and the recess formed in the housing, and the outer ring and the housing Is known (for example, see Patent Document 1).

JP 2006-226391 A

  However, in the four-point contact ball bearing described in Patent Document 1, the shape of the inclined surface formed on the outer ring has a simple structure, and thermal spraying of the insulating coating is relatively easy to perform, but additional work is required for the outer ring. Therefore, the number of processing steps is increased, the number of parts is increased because a fixing key is required, and further, the bearing has a problem of directivity.

  The present invention has been made in view of the above-described circumstances, and the object thereof is to increase the number of processing steps and the number of parts, and without causing directionality in the bearing, between the outer ring and the housing. An object of the present invention is to provide a four-point contact ball bearing capable of preventing creep.

The above object of the present invention can be achieved by the following constitution.
(1) An outer ring having an outer ring raceway surface on the inner peripheral surface, an inner ring having an inner ring raceway surface on the outer peripheral surface, and a plurality of balls arranged to be rollable between the outer ring raceway surface and the inner ring raceway surface, provided, the outer ring raceway surface and the inner ring raceway surface has a pair of side curved surface in contact with the ball, respectively, to a pair of side curved surface and balls come in contact with two points, the outer ring raceway surface center of the ball as a center point A four-point contact ball bearing with an angle from the axial center position to the contact position between the outer ring raceway surface and the ball as a rest angle α ₀ , which is used in an automobile transmission and is lubricated by lubricating oil circulating in the transmission. The outer ring outer circumferential surface is arranged in contact with the inner circumferential surface of the aluminum housing of the transmission, the outer ring wall thickness along the straight line extending in the direction of the rest angle α ₀ is Hα, the ball diameter is Da, the left and right rests extension to the angle α ₀ direction The axial width between the intersections of the straight line and the outer peripheral surface of the outer ring Biarufa, when the axial width of the outer ring and is B, so as to satisfy 0.42 Da ≦ Hα ≦ 0.67 Da, and Bα <B A four-point contact ball bearing characterized in that the curvature radius R of the side curved surface is set to 51% to 55% of the ball diameter Da, and the rest angle α ₀ is set to 20 ° to 28 ° .
(2) 0.42Da ≦ Hα ≦ 0.59Da is set to satisfy the four-point contact ball bearing according to rest angle alpha ₀ is characterized in that it is set to 25 ° ~28 ° (1).
(3) At least one of the outer ring raceway surface and the inner ring raceway surface, four-point contact ball bearing according to, further comprising a bottom tracks surface connecting smoothly the pair of side curved (1) or (2).
( 4 ) The four-point contact ball bearing according to ( 3 ), wherein an axial width Bw of the bottom curved surface is set to 1 mm to 2 mm.

According to the present invention, it is used in a transmission of an automobile and is lubricated by lubricating oil circulating in the transmission, and the outer peripheral surface of the outer ring is arranged in contact with the inner peripheral surface of the aluminum housing of the transmission, and the rest angle α ₀ Hα is the thickness of the outer ring along the straight line extending in the direction, Da is the diameter of the ball, Bα is the axial width between the intersection of the straight line extended in the left and right rest angle α ₀ direction and the outer peripheral surface of the outer ring, and the axis of the outer ring When the direction width is B, 0.42 Da ≦ Hα ≦ 0.67 Da and Bα <B are set, and the curvature radius R of the side curved surface is 51% to 55% of the ball diameter Da. The rest angle α ₀ is set to 20 ° to 28 °. For this reason, the rigidity of the outer ring can be ensured, and the undulation deformation of the outer ring due to repeated passage of balls can be suppressed to prevent creep between the outer ring and the housing. Further, no additional work is required on the outer ring, and it is not necessary to process one end portion of the outer peripheral surface of the outer ring. Therefore, there is no need for separate parts such as a fixed key, and there is no directionality in the bearing. Therefore, the outer ring and the housing can be produced without increasing the number of processing steps and the number of parts, and without causing directionality in the bearing. Creep between the two can be prevented.

It is principal part sectional drawing explaining one Embodiment of the 4-point contact ball bearing which concerns on this invention. It is sectional drawing of the outer ring | wheel and inner ring | wheel shown in FIG.

  Hereinafter, an embodiment of a four-point contact ball bearing according to the present invention will be described in detail based on the drawings.

  As shown in FIG. 1, the four-point contact ball bearing 10 of the present embodiment includes an outer ring 11 having an outer ring raceway surface 11a on an inner peripheral surface, an inner ring 12 having an inner ring raceway surface 12a on an outer peripheral surface, and an outer ring raceway surface 11a. And a plurality of balls 13 that are arranged so as to be able to roll between the inner ring raceway surface 12a and a cage 14 that holds the plurality of balls 13 so as to be able to roll. The four-point contact ball bearing 10 of the present embodiment is used, for example, in an automobile transmission, and is lubricated by lubricating oil circulating in the transmission.

  As shown in FIGS. 1 and 2, the outer ring raceway surface 11a has left and right side curved surfaces 15a that come into contact with the balls 13, and bottom curved surfaces 15b that smoothly connect the left and right side curved surfaces 15a. The side curved surface 15a and the ball 13 are in contact at two points. The inner ring raceway surface 12a has left and right side curved surfaces 16a that contact the balls 13, and a bottom curved surface 16b that smoothly connects the left and right side curved surfaces 16a. The left and right side curved surfaces 16a and the balls 13 are in contact at two points. ing. The outer ring raceway surface 11a and the inner ring raceway surface 12a have a Gothic arch shape.

In the present embodiment, the angle from the axial center position of the outer ring raceway surface 11a to the contact position between the left and right side curved surfaces 15a and the ball 13 with the center of the ball 13 as the center point P0 is a rest angle (ball contact angle) α. ₀ and to have, the rest angle alpha ₀ is set to 20 ° to 30 °.

In the present embodiment, the thickness of the outer ring 11 along the straight line L that extends in the rest angle alpha ₀ direction H-alpha, Da diameter of the ball 13, the left and right backrest angle alpha ₀ the straight line L and the outer ring 11 that extends in a direction When the axial width between the intersection points Px with the outer peripheral surface is Bα and the axial width of the outer ring 11 is B, 0.40 Da ≦ Hα ≦ 0.80 Da and Bα <B are set.

  Further, in the present embodiment, the axial widths Bw of the bottom curved surfaces 15b and 16b of the outer ring raceway surface 11a and the inner ring raceway surface 12a are respectively set to 1 mm to 2 mm. Further, the curvature radius R of the side curved surfaces 15a, 16a of the outer ring raceway surface 11a and the inner ring raceway surface 12a is set to 51% to 55% of the diameter Da of the ball 13. In addition, the code | symbol P in FIG. 2 is a curvature center of the side curved surfaces 15a and 16a. Further, in FIG. 2, only the center of curvature P and the radius of curvature R of the side curved surface 15a of the outer ring raceway surface 11a are shown. However, if this is reversed upside down, the center of curvature P and the curvature of the side curved surface 16a of the inner ring raceway surface 12a. Radius R.

When the rest angle α ₀ is set to 20 ° to 30 °, if Hα is set excessively, the outer diameter of the bearing and the outer ring width increase, so that a four-point contact ball bearing is used. The effect of downsizing the bearing, which is one of the purposes, cannot be obtained. Therefore, in this embodiment, in order to obtain the effect of downsizing the bearing, the range of Hα is set to 0.40 Da ≦ Hα ≦ 0.80 Da. Moreover, it is more preferable to set the range of Hα to 0.42 Da ≦ Hα ≦ 0.67 Da.

In the present embodiment, the straight line L extending in the direction of the left and right rest angles α ₀ and the outer peripheral surface of the outer ring 11 are provided so that sufficient outer ring wall thickness is ensured and sufficient support rigidity is obtained at the time of bearing load input. The axial width Bα (= 2 * (Hα + Da / 2) * sinα ₀ ) between the intersection points Px of the outer ring 11 is set to Bα <B with respect to the axial width B of the outer ring 11, and the rolling element load direction at the time of radial load input The outer ring outer peripheral surface and the housing inner peripheral surface are arranged on the inner surface. Therefore, the intersection Px is the surface of the outer peripheral surface of the straight line L and the outer ring 11 when, was extended to rest angle alpha ₀ direction chamfer 11b at an axial end of the outer peripheral surface of the outer ring 11 are present as in this embodiment It is preferable that it does not catch on the taking part 11b. In addition, the axial width B of the outer ring 11 of this embodiment does not include the axial width of the chamfered portion 11b, but the widthwise dimension of the cylindrical surface portion having the same radial dimension on the outer peripheral surface of the outer ring 11. It is.

As described above, according to the four-point contact ball bearing 10 of the present embodiment, H-alpha the thickness of the outer ring 11 along the straight line L that extends in the rest angle alpha ₀ direction, Da diameter of the ball 13, the left and right Rest Bα the axial width of the intersection Px between the outer peripheral surface of the straight line L and the outer ring 11 that extend to an angle alpha ₀ direction, when the axial width of the outer ring 11 was set to B, 0.40Da ≦ Hα ≦ 0.80Da, and Since it is set so as to satisfy Bα <B, it is possible to secure the rigidity of the outer ring 11, suppress the wavy deformation of the outer ring 11 due to repeated passage of the balls 13, and prevent creep between the outer ring 11 and the housing. it can. Further, no additional work is required for the outer ring 11, and it is not necessary to process one end portion of the outer peripheral surface of the outer ring 11. Accordingly, no separate parts such as a fixed key are required, and the bearing 10 does not have directionality. Therefore, the outer ring can be produced without increasing the number of processing steps and the number of parts and without causing the bearing 10 to have directionality. Creep between 11 and the housing can be prevented.

In order to confirm the effects of the present invention, four-point contact ball bearings of Examples 1 to 5 and Comparative Examples 1 to 3 shown in Table 1 below are prepared, and a rotation test is performed on each of them to generate outer ring creep. The presence or absence was confirmed. Incidentally, alpha ₀ is rest angle in Table 1, H-alpha is the thickness of the outer ring along a straight line extending in the rest angle direction, Da is the diameter of the ball.

  As is apparent from Table 1, creep occurred in Comparative Examples 1 to 3 having a Hα / Da ratio of less than 0.40, and creep occurred in Examples 1 to 5 having a Hα / Da ratio of 0.40 or more. I found that there was no Therefore, it was found that the range of Hα is preferably set to 0.40 Da ≦ Hα ≦ 0.80 Da, and the range of Hα is more preferably set to 0.42 Da ≦ Hα ≦ 0.67 Da.

In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.
For example, in this embodiment, a bottom curved surface that smoothly connects the left and right side curved surfaces is provided on both the outer ring raceway surface and the inner ring raceway surface, but the present invention is not limited to this, and the left and right side curved surfaces are provided only on the inner ring raceway surface. The bottom curved surface which connects smoothly may be provided.

10 Four-point contact ball bearing 11 Outer ring 11a Outer ring raceway surface 12 Inner ring 12a Inner ring raceway surface 13 Ball 14 Cage 15a Side curved surface 15b Bottom curved surface 16a Side curved surface 16b Bottom curved surface P0 Center point α ₀ Rest angle (ball contact angle)
L Straight line extended in rest angle direction Hα Thickness of outer ring along straight line extended in rest angle direction Da Ball diameter Px Intersection Bα Axial width between intersections B Outer ring axial width Bw Axial width of bottom curved surface P side Curvature center of curved surface R Curvature radius of curved surface

Claims (4)

An outer ring having an outer ring raceway surface on an inner peripheral surface, an inner ring having an inner ring raceway surface on an outer peripheral surface, and a plurality of balls arranged to be rollable between the outer ring raceway surface and the inner ring raceway surface. ,
The outer ring raceway surface and the inner ring raceway surface has a pair of side curved surface in contact with the ball, respectively, and the ball and the pair of side curved surface to come in contact at two points,
A four-point contact ball bearing in which an angle from an axial center position of the outer ring raceway surface to a contact position between the outer ring raceway surface and the ball is a rest angle α ₀ with the center of the ball as a center point;
Used in automobile transmissions, lubricated by lubricating oil circulating in the transmission,
An outer peripheral surface of the outer ring is disposed in contact with an inner peripheral surface of the aluminum housing of the transmission,
Hα the thickness of the outer ring along a straight line extending in the rest angle alpha ₀ direction,
The diameter of the ball is Da,
Bα represents the axial width between the intersections of the straight line extending in the direction of the left and right rest angle α ₀ and the outer peripheral surface of the outer ring
When the axial width of the outer ring is B,
0.42 Da ≦ Hα ≦ 0.67 Da and Bα <B are set .
The radius of curvature R of the side curved surface is set to 51% to 55% of the diameter Da of the ball,
4-point contact ball bearing, characterized in that said rest angle alpha ₀ is set to 20 ° ~ 28 °. 0.42 Da ≦ Hα ≦ 0.59 Da is set,
The rest angle α ₀ The four-point contact ball bearing according to claim 1, wherein is set to 25 ° to 28 °. The outer ring raceway surface and at least one of the inner ring raceway surface, four-point contact ball bearing according to claim 1 or 2, characterized in that pre-Symbol further has a bottom tracks surface smoothly connecting the pair of side surfaces. The four-point contact ball bearing according to claim 3 , wherein an axial width Bw of the bottom curved surface is set to 1 mm to 2 mm.

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