JP2023184054A - Rolling bearing device - Google Patents

Abstract

To inhibit smearing of a raceway surface of an inner ring in a rolling bearing device in which an outer ring rotates.SOLUTION: A rolling bearing device has: an undisplaceable shaft 88; a housing 82 which rotates relative to the shaft 88; and a rolling bearing 10 supporting the housing 82. The rolling bearing 10 includes: an inner ring 13 fixed to the shaft 88; an outer ring 12 fixed to the housing 82; and multiple rolling elements 14 assembled to a space between the outer ring 12 and the inner ring 13 in a rollable manner. The shaft 88 includes: a shaft part 34 on which the inner ring 13 is externally fitted; and a step part 89 which contacts with one axial side surface 27 of the inner ring 13 to restrict an axial position of the inner ring 13. An outer periphery at the upper side in a vertical direction of the step part 89 includes a recessed part 33 recessed to the radial inner side and extending in an axial direction. A lubrication oil for lubricating the rolling bearing 10 flows along the recessed part 33.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rolling bearing device in which a rotating body is rotationally supported by a rolling bearing, and particularly to a rolling bearing device using a rolling bearing in which an outer ring rotates and is lubricated with lubricating oil.

Patent Document 1 discloses a rolling bearing device 80 that is incorporated into an automobile transaxle 81 at a location indicated by arrow C in FIG. 7, and in which an outer ring of a rolling bearing 83 rotates. The rolling bearing 83 has an inner ring fixed to a case (shaft) 88, an outer ring fitted to the inner periphery of a counter drive gear (housing) 82, and the outer ring rotates together with the counter drive gear 82.

The transaxle 81 includes a first input shaft 84 that inputs power from the engine, a second input shaft 85 that inputs power from the motor, and a planetary mechanism 87, each of which rotates along the first rotation axis n. arranged in a straight line. When the first input shaft 84 and the second input shaft 85 rotate, the planetary mechanism 87 rotates the counter drive gear 82 .

The driving force of counter drive gear 82 is transmitted to differential gear 86. An oil tank (not shown) is provided below the differential gear 86. The oil tank stores lubricating oil G for lubricating the planetary mechanism 87 and the rolling bearing 83. The lubricating oil G is splashed up by the rotation of the differential gear 86 and is scattered around the outer periphery of the counter drive gear 82.

JP2013-061046A

The lubricating oil G is splashed on the outer periphery of the counter drive gear 82, and flows downward through a gap s1 between the case 88 and the counter drive gear 82, as shown by an arrow G1 in FIG.
At the bearing mounting portion where the rolling bearing 83 is assembled, a stepped portion 89 is provided to regulate the axial position of the inner ring. After the lubricating oil G flowing through the gap s1 reaches the stepped portion 89, part of the lubricating oil G is supplied to the rolling bearing 83, and the other lubricating oil G flows circumferentially around the outer periphery of the stepped portion 89. and reflux into the oil tank.

The lubricating oil G supplied to the rolling bearing 83 moves outward in the radial direction due to centrifugal force acting on the balls as they rotate and revolve, and as the outer ring rotates. For this reason, the amount of lubricating oil G retained on the inner ring raceway surface is reduced, and there is a risk that oil film formation between the balls and the inner ring raceway surface will be reduced. When oil film formation is reduced, smearing may occur on the raceway surface. Smearing is a form of damage to rolling bearings that occurs when sliding contact occurs between the rolling elements and the raceway surface, causing the lubricating oil film to break and the raceway surface to become rough.

Therefore, the present invention aims to suppress the occurrence of smearing on the inner ring raceway surface by increasing the amount of lubricating oil G supplied to the inner ring raceway surface in a rolling bearing device in which the outer ring of the rolling bearing rotates. There is.

One form of the present invention includes an undisplaceable shaft, a housing that rotates with respect to the shaft, and a rolling bearing that supports the housing, and the rolling bearing includes an inner ring fixed to the shaft; The housing includes an outer ring fixed to the housing, and a plurality of rolling elements rotatably incorporated between the outer ring and the inner ring, and the shaft has a shaft part on which the inner ring is fitted onto the outside. , a stepped portion that comes into contact with one axial side surface of the inner ring to regulate the axial position of the inner ring, and a bottom surface that is recessed radially inward on the outer periphery of the stepped portion in the vertical direction. The bearing is characterized in that it has a recess extending in the axial direction, and lubricating oil for lubricating the rolling bearing flows along the recess.

The rolling bearing device of the present invention in which the outer ring of the rolling bearing rotates can increase the amount of lubricating oil G supplied to the raceway surface of the inner ring. Thereby, the rolling bearing device of the present invention can suppress the occurrence of smearing on the inner ring raceway surface.

FIG. 1 is an axial cross-sectional view of a rolling bearing device according to the present invention. FIG. 3 is an enlarged front view of the vicinity of the recess. It is an explanatory view explaining the flow of lubricating oil inside a case. FIG. 2 is an explanatory diagram illustrating the flow of lubricating oil in a conventional transaxle. FIG. 7 is an axial cross-sectional view of a rolling bearing device according to a second embodiment. FIG. 7 is an axial cross-sectional view of a rolling bearing device according to a third embodiment. FIG. 2 is a partial cross-sectional view of a conventional automobile transaxle.

(First embodiment)
Embodiments of the present invention will be described using figures. A rolling bearing device 10 according to an embodiment of the present invention (hereinafter referred to as "first embodiment") is incorporated into an automobile transaxle and used for rotationally supporting a counter drive gear. The basic structure of the transaxle in which the rolling bearing device 10 is incorporated is the same as that of the prior art. Therefore, configurations common to those of the prior art will be described with reference to FIG. 7 and given the same numbers.
The rolling bearing device 10 of the first embodiment is installed on the first axial side of the counter drive gear 82 at a location indicated by arrow C in FIG.

FIG. 1 is an axial cross-sectional view of the rolling bearing device 10. As shown in FIG. The rolling bearing device 10 includes a rolling bearing 11, a case (shaft) 88, and a counter drive gear (housing) 82.
The central axis m of the rolling bearing 11 in FIG. 1 is parallel to the first rotation axis n in FIG. 7 . In the following explanation, the direction parallel to the central axis m of the rolling bearing 11 is the axial direction, the direction perpendicular to the central axis m is the radial direction, and the direction of rotation around the central axis m is the circumferential direction. direction. Further, in accordance with FIG. 7, the right side of FIG. 1 is the first side in the axial direction, and the left side is the second side in the axial direction.

(Rolling bearing)
The rolling bearing 11 is a deep groove ball bearing and includes an outer ring 12, an inner ring 13, balls 14 as a plurality of rolling elements, and a cage 15.

The outer ring 12 has an annular shape and is made of a steel material such as bearing steel. The outer ring 12 includes a bearing outer diameter surface 16, a pair of outer ring side surfaces 17, 17, an outer ring raceway surface 18, a third shoulder 19, and a fourth shoulder 20.

The bearing outer diameter surface 16 is a cylindrical surface centered on the central axis m. The outer ring side surface 17 on the first axial side extends radially inward from the end on the first axial side of the bearing outer diameter surface 16, and the outer ring side surface 17 on the second axial side The side surface 17 extends radially inward from the second axial end of the bearing outer diameter surface 16 . A pair of outer ring side surfaces 17, 17 each extend in a direction perpendicular to the central axis m and are parallel to each other.

The outer ring raceway surface 18 is formed on the inner circumference of the outer ring 12 at the center in the axial direction over the entire circumference, and the balls 14 roll when the rolling bearing 11 rotates. The axial cross section of the outer ring raceway surface 18 has an arcuate shape with the center concave radially outward. The radius of curvature of the circular arc is slightly larger than the radius of curvature of the outer peripheral surface of the ball 14.
The third shoulder 19 is provided on the first axial side of the outer raceway surface 18, and the fourth shoulder 20 is provided on the second axial side. The inner circumferential surface 21 of the third shoulder 19 and the inner circumferential surface 22 of the fourth shoulder 20 are both cylindrical surfaces centered on the central axis m, and have the same inner diameter.

The inner ring 13 has an annular shape and is made of a steel material such as bearing steel. The inner ring 13 includes a bearing inner diameter surface 26 , a pair of inner ring side surfaces 27 , 27 , an inner ring raceway surface 28 , a first shoulder 29 , and a second shoulder 30 .

The bearing inner diameter surface 26 is a cylindrical surface centered on the central axis m. The inner ring side surface 27 on the first axial side extends radially outward from the end of the bearing inner diameter surface 26 on the first axial side, and the inner ring side surface 27 on the second axial side 27 extends radially outward from the end on the second axial side of the bearing inner diameter surface 26. A pair of inner ring side surfaces 27, 27 each extend in a direction perpendicular to the central axis m and are parallel to each other.

The inner ring raceway surface 28 is formed at the center of the outer circumference of the inner ring 13 in the axial direction over the entire circumference, and the balls 14 roll when the rolling bearing 11 rotates. The axial cross section of the inner ring raceway surface 28 has an arcuate shape with the center concave radially inward. The radius of curvature of the circular arc is slightly larger than the radius of curvature of the outer peripheral surface of the ball 14.
The first shoulder 29 is provided on a first axial side of the inner raceway surface 28, and the second shoulder 30 is provided on a second axial side. The outer circumferential surface 31 of the first shoulder 29 and the outer circumferential surface 32 of the second shoulder 30 are both cylindrical surfaces centered on the central axis m, and have the same outer diameter.

The ball 14 is spherical and made of steel such as bearing steel. In the rolling bearing 11 of the first embodiment, eight balls 14 are installed at equal intervals in the circumferential direction.
The cage 15 is a corrugated cage, and is made by combining two corrugated annular parts manufactured by press-forming cold rolled steel plates such as SPCC so as to face each other, and fixing them to each other with rivets. . The retainer 15 has pockets that retain the balls 14 at equal intervals in the circumferential direction.

In this way, as shown in FIG. 1, the rolling bearing 11 is assembled with an outer ring 12 and an inner ring 13 with their central axes aligned, and a plurality of balls 14 are installed between the outer ring raceway surface 18 and the inner ring raceway surface 28. The balls 14 are held by a retainer 15 at equal intervals in the circumferential direction. In the rolling bearing 11, when the outer ring 12 rotates, the balls 14 revolve. The cage 15 rotates around the central axis m as the balls 14 revolve.

(Case)
The case 88 will be explained with reference to FIGS. 1 and 2.
FIG. 2 is a front view of the case 88 viewed in the direction indicated by the outline arrow A in FIG. 1 with the rolling bearing 11 removed.

Please refer to FIG. The case 88 includes a first case body 91, a bearing mounting portion 35 for mounting the rolling bearing 11, and a recess 33 for causing the lubricating oil G to flow toward the rolling bearing 11. The bearing mounting portion 35 includes a shaft portion 34 and a step portion 89 that restricts the position of the rolling bearing 11 in the axial direction. The case 88 is manufactured by casting using an aluminum alloy, and the first case body 91, the bearing mounting portion 35, and the recess 33 are integrally formed.
As shown in FIG. 7, the case 88 is axially connected to a second case 92 disposed on the second axial side. The case 88 and the second case 92 are combined with each other in the axial direction to form a case that tightly covers the planetary mechanism 87 and the differential gear 86. In the following description, the space on the side where the planetary mechanisms and the like of each case 88 and 92 are installed is the inner periphery of the case.

The bearing mounting portion 35 will be explained. The shaft portion 34 has a substantially cylindrical shape centered on the central axis m, and extends from the second axial side of the stepped portion 89 toward the second axial side with a length equivalent to the bearing width of the rolling bearing 11. It has been extended. The shaft portion 34 includes an inner ring fitting surface 34a and an end surface 34b. The inner ring fitting surface 34a is a cylindrical surface extending in the axial direction parallel to the central axis m, and the diameter of the inner ring fitting surface 34a is equivalent to the inner diameter of the bearing inner diameter surface 26 of the rolling bearing 11. The end surface 34b extends radially inward from the second axial end of the inner ring fitting surface 34a in a direction perpendicular to the central axis m.
The bearing inner diameter surface 26 of the rolling bearing 11 is fitted onto the outer periphery of the shaft portion 34 . The shaft portion 34 has a predetermined thickness in the radial direction so as to be able to support the load acting on the rolling bearing 11.

The stepped portion 89 has a shape that is uniformly raised in the circumferential direction from the inner surface of the first case main body 91 toward the second side in the axial direction. When viewed in the axial direction in the direction indicated by the white arrow A in FIG. 1, the stepped portion 89 has an annular shape centered on the central axis m, as shown in FIG. The step portion 89 has a bearing contact surface 38 over the entire circumference, and has a step outer circumferential surface 39 except for the area where the recess 33 is formed.

The bearing contact surface 38 extends radially outward from the first axial end of the inner ring fitting surface 34a in a direction perpendicular to the central axis m. The bearing contact surface 38 comes into contact with the inner ring side surface 27 when the rolling bearing 11 is assembled, and regulates the position of the rolling bearing 11 in the axial direction.
The stepped outer circumferential surface 39 is a cylindrical surface centered on the central axis m, and extends parallel to the central axis m from the radially outer end of the bearing contact surface 38 toward the first side in the axial direction. are doing. In this embodiment, the outer diameter of the step outer peripheral surface 39 is smaller than the outer diameter of the first shoulder 29 of the inner ring 13, but is not limited to this, and is smaller than the outer diameter of the first shoulder 29 of the inner ring 13. They may be larger or may be the same.

The first case body 91 is formed in a direction substantially perpendicular to the central axis m in the vicinity of the bearing mounting part 35, and the inner surface of the first case body 91 has a region in which the recess 33 is formed. Except for the step part outer circumferential surface 39, it is connected to the first axial end of the stepped part outer circumferential surface 39.

The recess 33 will be explained with reference to FIG. The recess 33 is arranged above the step 89 in the vertical direction. The vertical direction refers to a direction that corresponds to the vertical direction when the transaxle 81 is mounted on a vehicle such as an automobile and the vehicle is held in a normal driving position.
The recess 33 is defined in the circumferential direction by a first protrusion 41 and a second protrusion 42 that protrude from the step outer peripheral surface 39 in the vertical direction. The area sandwiched in the circumferential direction is recessed inward in the radial direction.

The first protrusion 41 is disposed on the first side in the circumferential direction from the vertically uppermost position of the stepped portion 89 (see FIG. 2). The second protrusion 42 is disposed on the second circumferential side from the vertically uppermost position of the step 89.
The first protrusion 41 and the second protrusion 42 each have a flat plate shape having a predetermined thickness in the circumferential direction, and have the same shape. The recesses 33 are arranged symmetrically with respect to a plane p that includes the central axis m and extends in the vertical direction. The distance between the first protrusion 41 and the plane p is equal to the distance between the second protrusion 42 and the plane p, and the first protrusion 41 and the second protrusion 42 are parallel to each other. Hereinafter, the first protrusion 41 will be explained, and the explanation of the second protrusion 42 will be omitted.

The first protrusion 41 has a substantially rectangular shape when viewed in the circumferential direction in the direction indicated by the white arrow B in FIG. The first protrusion 41 has a radially inner end connected to the step outer circumferential surface 39 over the entire axial region, and a first axial end connected to the step outer peripheral surface 39 over the entire radial region of the first case. It is connected to the main body 91.
The second axial side surface 43 of the first protrusion 41 is a plane that is perpendicular to the central axis m and extends vertically upward from the position of the step outer circumferential surface 39, and is a bearing abutting surface. It is on the same level as 38. Further, the radially outer upper surface 44 of the first protrusion 41 is perpendicular to the plane p and parallel to the central axis m.

The upper surface 44 of the first protrusion 41 is disposed so as to protrude upward in the vertical direction from at least the outer periphery of the first shoulder 29 of the inner ring 13, but in this embodiment, the upper surface 44 of the first protrusion 41 does not come into contact with the outer ring 12. The third shoulder 19 of the outer ring 12 is disposed at a position close to the inner circumferential surface 21 thereof. In FIG. 2, the position of the inner circumferential surface 21 of the third shoulder 19 of the outer ring 12 when the rolling bearing 11 is assembled to the bearing mounting portion 35 is indicated by a chain line.
By arranging the first protrusion 41 in a position close to the inner circumferential surface 21 of the third shoulder 19 of the outer ring 12, the volume of the recess 33 can be increased. Increasing the volume of the recess 33 leads to increasing the amount of lubricating oil G flowing out from the recess 33. Further, the first protrusion 41 does not interfere with the outer ring 12. When the outer ring 12 rotates, the occurrence of abnormal noises and vibrations caused by the first protrusion 41 interfering with the outer ring 12 is prevented.

The first protrusion 41 and the second protrusion 42 are connected in the circumferential direction by a recess bottom surface 46 and a recess back surface 47. The recessed portion back surface 47 is a plane radially inward from the imaginary line t connecting the upper surface 44 of the first protrusion 41 and the upper surface 44 of the second protrusion 42 in FIG. 2 . In the rolling bearing device 10 of the first embodiment, the recessed portion back surface 47 is a flat surface that is continuous with the inner circumferential surface of the first case body 91.
The recess bottom surface 46 is arranged at a position recessed inward in the radial direction from the upper surface 44 of the first protrusion 41 and the upper surface 44 of the second protrusion 42 . The recess bottom surface 46 is inclined toward the central axis m as it advances toward the second side in the axial direction. The second axial end of the recess bottom surface 46 is connected to the radially outer end of the bearing contact surface 38, and the first axial end of the recess bottom surface 46 is connected to the radially outer end of the bearing contact surface 38. It is connected to the radially inner end of the back surface 47.
In this way, the recess 33 is defined by the first protrusion 41, the second protrusion 42, the recess bottom surface 46, and the recess back surface 47, and constitutes a groove that is depressed inward in the radial direction and extends in the axial direction. ing. As will be described later, the lubricating oil G that lubricates the rolling bearing 11 flows along the recess 33.

(Counter drive gear)
Please refer to FIGS. 1 and 7. The counter drive gear 82 has a substantially cylindrical shape centered on the central axis m, and includes an externally toothed gear 90 that meshes with the differential gear 86 on its outer periphery. The counter drive gear 82 is driven by a planetary mechanism 87 built into the inner circumferential side and rotates about the central axis m when the vehicle is running.
The counter drive gear 82 includes a fitting portion on the inner periphery of the first end in the axial direction, into which the outer ring 12 of the rolling bearing 11 is assembled. The fitting portion includes an outer ring fitting surface 50 extending parallel to the center axis m from an end surface 49 on a first side in the axial direction, and a center extending from an end on a second side in the axial direction of the outer ring fitting surface 50. A bearing contact surface 51 extends radially inward in a direction perpendicular to the axis m. The inner diameter of the outer ring fitting surface 50 is equivalent to the outer diameter of the bearing outer diameter surface 16 of the rolling bearing 11. The distance in the axial direction between the end surface 49 and the bearing contact surface 51 is equivalent to the bearing width of the rolling bearing 11.

Therefore, the outer ring side surface 17 and the end surface 49 of the counter drive gear 82 are assembled substantially flush. The inner circumferential surface of the first case body 91 is separated from the inner ring side surface 27 by the axial length of the step outer circumferential surface 39 toward the first side in the axial direction, so that the axial clearance s1 is It is formed between the end surface 49 of the counter drive gear 82 and the inner peripheral surface of the first case main body 91. The lubricating oil G splashed up by the differential gear 86 flows toward the rolling bearing 11 through the gap s1.
The other configurations of the counter drive gear 82 are the same as those of the conventional counter drive gear 82, and a description thereof will be omitted.

(Rolling bearing device)
Next, the effects of the rolling bearing device 10 of the first embodiment will be explained with reference to FIG.
3(a) is a partial sectional view of the rolling bearing device 10 similar to FIG. 1, and FIG. 3(b) is a front view of the vicinity of the recess 33 similar to FIG. It is an explanatory view explaining the flow of lubricating oil G in the periphery.

When the differential gear 86 rotates, the lubricating oil G splashed up scatters around the outer periphery of the counter drive gear 82 (see FIG. 7).
As shown in FIG. 3, the scattered lubricating oil G flows vertically downward through the gap s1 (arrow G1). Some of the lubricating oil G flows into the circumferentially inner side of the recess 33 (the area sandwiched between the first protrusion 41 and the second protrusion 42) and rolls along the bottom surface 46 of the recess. It flows toward the inner ring 13 of the bearing 11 (arrow G2). In the rolling bearing device 10 of the first embodiment, the second axial end of the recess bottom surface 46 and the first shoulder 29 of the inner ring 13 are formed at the same position in the radial direction. The lubricating oil G that has flowed on the bottom surface 46 of the recess quickly flows toward the rolling bearing 11 .
Furthermore, the lubricating oil G flowing to the outside of the recess 33 in the circumferential direction (the first side in the circumferential direction from the first protrusion 41 or the second side in the circumferential direction from the second protrusion 42) , as indicated by the broken line (arrow G3) in FIG. It refluxes to the oil tank No. 81.

The effect of the recess 33 according to the present invention will be explained with respect to the flow of lubricating oil G in comparison with the case where the step 89 is not provided with the recess 33. FIG. 4 is an explanatory diagram similar to FIG. 3 for explaining the flow of lubricating oil G, and shows the flow of lubricating oil G in the conventional rolling bearing device 80.
As shown in FIG. 4, the step outer circumferential surface 39 of the first case body 91 of the conventional rolling bearing device 80 is formed of a continuous cylindrical surface over the entire circumference. The step outer circumferential surface 39 is a cylindrical surface centered on the central axis m and extends in the axial direction parallel to the central axis m.

The lubricating oil G (arrow G1) that has flowed vertically downward through the gap s1 flows in, for example, a direction parallel to a plane p that includes the central axis m and extends vertically, and flows in the vertical direction of the stepped portion 89. When reaching the top of the lubricating oil G, most of the lubricating oil G separates and flows on both sides in the circumferential direction. Since the conventional first case body 91 is not provided with a protrusion (corresponding to the first protrusion 41 and the second protrusion 42), the amount of lubricant G is larger than that of the present invention. It flows in the circumferential direction along the step outer peripheral surface 39 (arrow G3).
In this way, most of the lubricating oil G flowing in through the gap s1 returns to the oil tank through the outer periphery of the stepped portion 89, so that the amount of lubricating oil G supplied to the rolling bearing 11 is not sufficient.

On the other hand, in the rolling bearing device 10 of the first embodiment, the first protrusion 41 and the second protrusion 42 are installed on both sides in the circumferential direction with the plane p interposed therebetween. Therefore, for example, when the lubricating oil G flows into the recess 33 from above the step 89 in a direction parallel to the plane p, the lubricating oil G is prevented from flowing in the circumferential direction, so that the lubricating oil G flows into the recess. More of the lubricating oil G flowing into the rolling bearing 33 flows in the axial direction toward the rolling bearing 11 than in the conventional rolling bearing device 80 (arrow G2).

Furthermore, since the recess bottom surface 46, which is the bottom surface of the recess 33, is inclined vertically downward toward the rolling bearing 11, the lubricating oil G in the recess 33 is axially directed toward the rolling bearing 11 with more force. Flow to. Further, at the second end of the recess bottom surface 46 in the axial direction, the recess bottom surface 46 and the outer peripheral surface 31 of the first shoulder 29 of the inner ring 13 are arranged at the same position in the radial direction. The flow of the lubricating oil G is not hindered by steps or the like, and the lubricating oil G quickly flows toward the rolling bearing 11.
However, the recess bottom surface 46 is not limited to the slope as described above, and the recess bottom surface 46 may be parallel to the central axis m, for example. By providing the first protruding part 41 and the second protruding part 42, it is possible to suppress the lubricating oil G from flowing in the circumferential direction around the outer periphery of the stepped part 89 and directly returning to the oil tank. The rolling bearing device 10 can increase the amount of lubricating oil G flowing toward the rolling bearing 11 and supply more lubricating oil G to the inner ring raceway surface 28.

In this way, the rolling bearing device 10 of the first embodiment causes the splashed lubricating oil G to flow into the recess 33, and the lubricating oil G is efficiently supplied toward the rolling bearing 11. Therefore, the rolling bearing device 10 of the first embodiment can increase the amount of lubricating oil G supplied to the inner ring raceway surface 28 of the inner ring 13, so that when the outer ring 12 rotates, the inner ring raceway surface 28 Occurrence of smearing can be suppressed.

(Second embodiment)
FIG. 5 is an axial sectional view similar to FIG. 1 of the rolling bearing device 10 of the second embodiment.
In the first embodiment, the side surface 43 on the second axial side of each of the protrusions 41 and 42 is flush with the bearing contact surface 38 . However, the rolling bearing device of the present invention is not limited to this, and as shown in FIG. It may protrude further toward the second axial side. As a result, the lubricating oil G flowing through the recess 33 is guided to the vicinity of the inner ring raceway surface 28 , so that the rolling bearing device 10 of the second embodiment directs the lubricating oil G toward the inner ring raceway surface 28 of the inner ring 13 . It can be supplied more efficiently.
Note that the radially inward end of the portion of each of the protrusions 41 and 42 that protrudes from the bearing contact surface 38 toward the second side in the axial direction can be connected to the outer circumferential surface 31 of the first shoulder 29 of the inner ring 13. It is preferable to make them as close to each other in the radial direction as possible.

(Third embodiment)
FIG. 6 is an axial cross-sectional view similar to FIG. 1 of the rolling bearing device 10 of the third embodiment.
In the first embodiment, the radially outer ends of each of the protrusions 41 and 42 are arranged close to the inner circumferential surface 21 of the third shoulder 19 of the outer ring 12 to the extent that they do not come into contact with the outer ring 12. There is. However, the rolling bearing device of the present invention is not limited to this, and the extended portion 52 continuous to each of the protrusions 41 and 42 of the first embodiment is integrally formed above each of the protrusions 41 and 42 in the vertical direction. It may be provided. The respective protrusions 41 and 42 and the expanded portion 52 may extend radially outward from the position of the inner circumferential surface 21 of the third shoulder 19 of the outer ring 12 as a whole. In this case, as shown in FIG. 6, the side surface 53 on the second axial side of the extended portion 52 is shifted toward the first side in the axial direction from the side surface 43 of each protrusion 41, 42, It does not come into contact with the outer ring 12.
Thus, in the rolling bearing device 10 of the third embodiment, the volume of the recess 33 can be increased by increasing the height of each of the protrusions 41 and 42 and the extended portion 52, and the lubricating oil G supplied to the rolling bearing 11 can be increased. The amount can be increased.

Further, although not shown, in the rolling bearing device 10 of the third embodiment, the pair of circumferentially facing extended portions 52, 52 may be inclined so as to be farther away from each other as they move outward in the vertical direction. . By doing so, a large amount of the lubricating oil G flowing vertically downward can be guided to the recess 33 through the gap s1, so that the rolling bearing device 10 of the third embodiment can direct the lubricant G flowing downward to the rolling bearing 11. The amount of oil G can be further increased,

The present invention has been described above using the rolling bearing device 10 incorporated in the first axial side of the counter drive gear 82 as an example according to the first to third embodiments. Similarly, the rolling bearing device 10 according to the invention can also be incorporated on the second axial side of the counter drive gear 82. The fourth embodiment is a form in which the rolling bearing device 10 of the first embodiment is incorporated on the second axial side of a counter drive gear 82. Since the form of the recess 33a on the second axial side is similar to the form of the recess 33 on the first axial side, it will be briefly described with reference to FIGS. 1 and 2. Note that the reference numerals assigned to the structures on the second axial side are distinguished by adding "a" to the reference numerals of the corresponding structures on the first axial side.

On the second axial side, the second recess 33a is formed at the top of the second step 89a formed in the second case 92 in the vertical direction. The second recess 33a is defined by a pair of protrusions 41a and 42a that protrude vertically upward from the outer periphery of the second step 89a, a second recess bottom surface 46a, and a second recess back surface 47a. and is recessed radially inward and extends axially. The recessed portion back surface 47a may be a flat surface continuous with the inner circumferential surface of the second case main body 91a.
In this way, the lubricating oil G passes through the gap s2 between the counter drive gear 82 and the second case 92, flows into the second recess 33a flowing vertically downward, and then flows toward the second rolling bearing 11a. Flow. In this way, the rolling bearing device 10a of the fourth embodiment causes the splashed lubricating oil G to flow into the recess 33a, and the lubricating oil G is efficiently supplied toward the rolling bearing 11a. Therefore, the rolling bearing device 10a of the fourth embodiment can increase the amount of lubricating oil G supplied to the inner ring raceway surface 28a of the inner ring 13a, so that when the outer ring 12a rotates, the inner ring raceway surface 28a Occurrence of smearing can be suppressed. The other configurations and effects are the same as those of the first embodiment, so their explanations will be omitted.

Although the embodiments of the present invention have been described above, each embodiment is merely an example, and various changes can be made without departing from the spirit of the present invention.
For example, the rolling bearing 11 incorporated in the rolling bearing device 10 has been described using a deep groove ball bearing in which the rolling elements are balls, but the rolling elements may be cylindrical rollers, tapered rollers, or spherical rollers. Moreover, although the case where it is incorporated in the transaxle 81 of an automobile has been described, it may be used in other devices used for rotating outer wheels.
In addition, each embodiment describes the configuration and effects of each part when the axis (hereinafter referred to as the "reference axis") that is on the plane p and perpendicular to the central axis m is arranged in the same direction as the vertical direction. There is. However, in actual use, the reference axis is not limited to being geometrically oriented in the vertical direction. Of course, the same adoption effect can be obtained even if the reference axis is inclined at a predetermined angle with respect to the vertical direction. Therefore, it is preferable that the angle between the reference axis and the vertical direction is 45 degrees or less, although this does not prevent the reference axis from being used in an inclined state with respect to the vertical direction.

(Embodiment) 10: Rolling bearing device, 11: Rolling bearing, 12: Outer ring, 13: Inner ring, 14: Balls, 15: Cage, 16: Bearing outer diameter surface, 17: Outer ring side surface, 18: Outer ring raceway surface, 19: Third shoulder (outer ring), 20: Fourth shoulder (outer ring), 26: Bearing inner diameter surface, 27: Inner ring side surface, 28: Inner ring raceway surface, 29: First shoulder (inner ring), 30: No. 2 shoulder (inner ring), 33: recessed portion, 34: shaft portion, 34a: inner ring fitting surface, 34b: end surface, 35: bearing mounting portion, 38: bearing abutting surface, 39: stepped outer peripheral surface, 41: No. 1 protrusion, 42: second protrusion, 43: side surface, 44: upper surface, 46: recess bottom surface, 47: recess back surface, 49: end surface (counter drive gear), 50: outer ring fitting surface, 51: Bearing contact surface, 52: extension part,
(Prior art) 80: Rolling bearing device, 81: Transaxle, 82: Counter drive gear (housing), 83: Rolling bearing, 84: First input shaft, 85: Second input shaft, 86: Differential gear, 87: Planetary mechanism, 88: case, 89: step, 90: gear, 91: first case body, 91a: second case body, 92: second case

Claims (3)

an immovable axis;
a housing that rotates about the axis;
a rolling bearing that supports the housing;
The rolling bearing includes an inner ring fixed to the shaft;
an outer ring fixed to the housing;
a plurality of rolling elements rotatably incorporated between the outer ring and the inner ring,
The shaft includes a shaft portion onto which the inner ring is externally fitted, and a stepped portion that comes into contact with one axial side surface of the inner ring to regulate the axial position of the inner ring,
A recessed portion having a bottom surface recessed inward in the radial direction and extending in the axial direction is provided on the outer periphery of the stepped portion in the vertical direction, and lubricating oil for lubricating the rolling bearing flows along the recessed portion. A rolling bearing device characterized by: The recess is defined in the circumferential direction by a first protrusion and a second protrusion that respectively protrude vertically upward from the outer periphery of the step,
The first protruding portion protrudes vertically above one shoulder in the axial direction of the inner ring on a first side in the circumferential direction from the uppermost side in the vertical direction of the step portion,
The second protruding portion protrudes vertically above the one shoulder in the axial direction of the inner ring on a second side in the circumferential direction from the uppermost side in the vertical direction of the step portion,
The rolling bearing device according to claim 1, wherein the bottom surface connects the first protrusion and the second protrusion in the circumferential direction at a position recessed inward in the radial direction. The bottom surface is inclined in such a direction that the other end in the axial direction is located vertically lower than the one end in the axial direction, and is radially outward from the one shoulder in the axial direction of the inner ring. The rolling bearing device according to claim 1 or 2, characterized in that:

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