JP2018044576A - Rolling bearing for drive unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing for a drive unit capable of making rotation resistance resulting from kinetic viscosity of lubricant small in activation under low-temperature environment, and also capable of securing excellent lubrication performance.SOLUTION: A holder 20 includes a pair of guide surfaces 21a, 21a that employs an outer ring guide system, and is guided to an inner peripheral surface of an outer ring 11 on both sides in an axial direction. On the pair of guide surfaces 21a, 21a of the holder 20, formed are plural recess grooves 23 provided as many as cylindrical rollers 15 at an equal interval in a circumferential direction, and respectively positioned on the same phase on both sides in the axial direction. Each recess groove 23 has a single circular arc shape. Each recess groove 23 is formed so that its circumferential intermediate part coincides with a circumferential phase of a center Or of the cylinder roller 15.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rolling bearing for a driving device, and more particularly to a rolling bearing for a driving device used in a driving device such as a railway vehicle such as a gear device.

In a conventional railway vehicle drive device (gear device), oil accumulated in the device is scooped up with a large gear, and the scooped oil is sprayed into the bearing to lubricate the rolling bearing. .

  For example, in the roller bearing described in Patent Document 1, as shown in FIG. 5, in the cage 114 guided by the flange portion 115 of the inner ring 111, the concave portions 117 are formed at equal intervals in the circumferential direction on the guide surface of the cage 114. A plurality are provided. As a result, the lubricating oil easily enters the guide surface of the cage 114 and the inside of the roller bearing, and appropriate bearing cooling is performed.

JP 2003-194066 A

By the way, in the conventional railway vehicle drive device (gear device), particularly at the time of cold start,
When the kinematic viscosity of the oil increases and high-viscosity oil enters the bearing, it behaves as a stirring resistance. For this reason, when the load is not fully applied, there is a possibility that problems such as revolving slip may occur in the cage. In addition, when starting at a low temperature, there is also a problem that the oil pumped up by the gears is difficult to enter the bearing.

In the roller bearing described in Patent Document 1, by using the cage 114 as an inner ring guide, a driving force due to rotation of the inner ring is applied to the cage 114 to prevent revolving slip of the cage 114. In addition, since the retainer 114 is provided with a plurality of recesses 117, the oil enters the bearing and discharges the oil from the bearing. However, more efficient oil supply to the inside of the bearing is further desired at the start-up in a low temperature environment.

The present invention has been made in view of the above circumstances, and its purpose is to reduce rotational resistance due to the kinematic viscosity of the lubricant at the time of start-up in a low-temperature environment, and drive with good lubrication performance. It is providing the rolling bearing for apparatuses.

The above object of the present invention can be achieved by the following constitution.
(1) An outer ring, an inner ring, a plurality of rolling elements that are rotatably arranged between raceways of the outer ring and the inner ring, and a cage that holds the plurality of rolling elements at a predetermined interval in the circumferential direction; The cage is an outer ring guide system, and includes a pair of guide surfaces guided on the inner peripheral surface of the outer ring on both axial sides, and the pair of guides of the cage The surface is provided with a plurality of concave grooves that are the same number as the rolling elements, are provided at equal intervals in the circumferential direction, and are positioned in the same phase on both sides in the axial direction. The rolling bearing for a driving device according to claim 1, wherein the groove has a circular arc shape, and each of the concave grooves is formed such that a circumferential intermediate portion thereof coincides with a circumferential phase of a center of the rolling element.
(2) The depth of each concave groove is 16 to 22% of the radial thickness of the cage, and the angle θ connecting the circumferential ends of the concave grooves from the center of the cage is 360. ° / (2.5 × number of rolling elements) ≦ θ ≦ 360 ° / (2 × number of rolling elements), groove cross-sectional area × number of rolling elements = 1.5 to 3.6 × guide gap cross-sectional area The rolling bearing for a drive device according to (1), characterized in that:

According to the rolling bearing for a driving device of the present invention, the cage is an outer ring guide system, and is provided with a pair of guide surfaces guided to the inner peripheral surface of the outer ring on both sides in the axial direction. Are formed in the same number as the rolling elements in the circumferential direction, and are formed with a plurality of concave grooves positioned in the same phase on both sides in the axial direction. Each concave groove has a single circular arc shape, and each concave groove is formed such that its circumferential intermediate portion coincides with the circumferential phase at the center of the rolling element. Thereby, at the time of starting in a low temperature environment, the rotational resistance resulting from the kinematic viscosity of the lubricant can be reduced, and good lubrication performance can be provided.

It is sectional drawing which shows the rolling bearing for drive devices which concerns on 1st Embodiment of this invention. It is a side view of the rolling bearing for drive devices of FIG. (A) is a principal part enlarged view which shows the holder | retainer and rolling element of FIG. 2, (b) is a principal part enlarged view for demonstrating the relationship between a guide clearance cross-sectional area and a ditch | groove cross-sectional area. It is sectional drawing which shows the rolling bearing for drive devices which concerns on 2nd Embodiment of this invention. It is a side view which shows the conventional inner ring | wheel and a holder | retainer.

  Hereinafter, a rolling bearing for a driving device according to each embodiment of the present invention will be described in detail with reference to the drawings.

(First embodiment)
As shown in FIGS. 1 and 2, the rolling bearing for a driving device of the first embodiment is a cylindrical roller bearing 10 that supports a gear device that is a driving device of a railway vehicle. The cylindrical roller bearing 10 includes an outer ring 11, an inner ring 12, a cylindrical roller 15 that is a plurality of rolling elements that are rotatably disposed between raceway surfaces 13 and 14 of the outer ring 11 and the inner ring 12, and the plurality of cylindrical rollers. And a retainer 20 for retaining 15 at predetermined intervals in the circumferential direction.

The outer ring 11 has a pair of flanges 16 projecting inward in the radial direction of the bearing on both axial sides of the outer ring raceway surface 13.

For example, brass, resin, steel, or the like can be applied to the cage 20, and the material is not limited. The cage 20 includes a pair of annular portions 21 and 21 provided on both sides in the axial direction, and a plurality of column portions 22 that couple the pair of annular portions 21 and 21 at predetermined intervals in the circumferential direction. .
The cage 20 is an outer ring guide system, and includes a pair of guide surfaces 21 a and 21 a that are guided to the inner peripheral surface of the flange portion 16 of the outer ring 11 by a pair of annular portions 21 and 21 on both sides in the axial direction. Thereby, the driving force by rotation of the outer ring is applied to the retainer 20, and the revolving slip of the retainer 20 is prevented.

  Further, the pair of guide surfaces 21a, 21a of the cage 20 are provided with the same number of the cylindrical rollers 15 at equal intervals in the circumferential direction, and a plurality of concaves respectively positioned in the same phase on both sides in the axial direction. Grooves 23, 23 are formed. Since the cage 20 is an outer ring guide, the clearance between the guide surfaces 21a and 21a of the cage 20 and the inner peripheral surface of the flange portion 16 of the outer ring 11 is reduced, but oil can be easily supplied from one of the concave grooves 23. The cylindrical roller bearing 10 is lubricated. Moreover, the oil which lubricated the cylindrical roller bearing 10 is discharged | emitted from each other recessed groove 23. FIG. Furthermore, by providing the concave grooves 23 in all rolling element phases in this way, a larger oil inflow area (or oil drainage area) can be ensured compared to the case without the concave grooves, Emission can be improved.

  As shown in FIG. 3A, each concave groove 23 is formed such that its circumferential intermediate portion coincides with the circumferential phase of the center Or of the cylindrical roller 15. Therefore, the lubricating oil (lubricant) can be expected to be written from the concave grooves 23 by the rotation of the cylindrical roller 15.

  Further, since each concave groove 23 has a single circular arc shape, the rotational resistance due to the kinematic viscosity of the lubricant can be reduced during start-up in a low-temperature environment, and good lubricating performance can be ensured. In particular, the depth h of each groove 23 is 16 to 22% of the radial thickness H of the cage 20, and the angle θ connecting the circumferential direction both ends of each groove 23 from the center O of the cage 20 is 360 ° / (2.5 × number of rolling elements) ≦ θ ≦ 360 ° / (2 × number of rolling elements). Moreover, as shown in FIG.3 (b), it sets to the ditch | groove cross-sectional area A2 x the number of rolling elements = 1.5-3.6 x guide clearance cross-sectional area A1. 3B represents a part of the cross-sectional area A1 formed over the entire circumference. Furthermore, each concave groove 23 is formed between the portions where the adjacent column portions 22 are connected in the annular portions 21 and 21. Thereby, each concave groove 23 can be easily processed, and the rigidity of the cage 20 is also ensured.

According to the cylindrical roller bearing 10 of the present embodiment configured as described above, the cage 20 is an outer ring guide system, and a pair of guide surfaces 21a guided to the inner peripheral surface of the outer ring 11 on both axial sides. A plurality of guide surfaces 21a, 21a of the cage 20 are provided in the same number as the cylindrical rollers 15 at equal intervals in the circumferential direction, and are positioned in the same phase on both sides in the axial direction. The concave groove 23 is formed. Each concave groove 23 has a single arc shape, and each concave groove 23 is formed such that its circumferential intermediate portion coincides with the circumferential phase of the center Or of the cylindrical roller 15. Thereby, at the time of starting in a low temperature environment, the rotational resistance resulting from the kinematic viscosity of the lubricant can be reduced, and good lubrication performance can be ensured.

(Second Embodiment)
Next, with reference to FIG. 4, the four-point contact ball bearing 10a of 2nd Embodiment is demonstrated. The four-point contact ball bearing 10 a of the second embodiment includes an outer ring 11, an inner ring 12, and balls 17 that are a plurality of rolling elements that are rotatably arranged between the raceways 13 a and 14 a of the outer ring 11 and the inner ring 12. And a cage 20 for holding the plurality of balls 17 in the circumferential direction at a predetermined interval. In addition, the outer ring raceway surface 13a and the inner ring raceway surface 14a of the present embodiment are formed in line symmetry with respect to the intermediate portion in the axial direction so as to contact the ball 17 at two points.

  The cage 20 includes a pair of annular portions 21 and 21 provided on both sides in the axial direction, and a plurality of column portions 22 that connect the pair of annular portions 21 and 21 at predetermined intervals in the circumferential direction. The ball 17 is held by a circular pocket. The cage 20 is an outer ring guide system, and the pair of guide surfaces 21a and 21a on the outer peripheral surface of the pair of annular portions 21 and 21 on both sides in the axial direction are inside the shoulder portions 18 on both sides in the axial direction of the outer ring 11. Guided to the circumference.

Also in this case, as in the first embodiment, the pair of guide surfaces 21a and 21a of the cage 20
A plurality of concave grooves 23, 23 are formed in the same number as the balls 17, provided at equal intervals in the circumferential direction, and positioned in the same phase on both sides in the axial direction. The shape of each concave groove 23 is the same as that of the first embodiment.

  Therefore, also in the four-point contact ball bearing 10a of the present embodiment, the cage 20 is an outer ring guide system, and includes a pair of guide surfaces 21a and 21a guided to the inner peripheral surface of the outer ring 11 on both axial sides. The pair of guide surfaces 21a and 21a of the cage 20 has a plurality of concave grooves 23 provided at equal intervals in the circumferential direction and at the same number on both sides in the axial direction. It is formed. Each concave groove 23 has a single arc shape, and each concave groove 23 is formed such that its circumferential intermediate portion coincides with the circumferential phase of the center Or of the ball 17. Thereby, at the time of starting in a low temperature environment, the rotational resistance resulting from the kinematic viscosity of the lubricant can be reduced, and good lubricating performance can be ensured.

  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.

  In the present embodiment, the cylindrical roller bearing and the four-point contact ball bearing have been described as the driving device rolling bearing. However, the present invention is not limited to this, and may be applied to other types of rolling bearings. It may be a ball bearing.

10 Cylindrical roller bearing (rolling bearing for drive unit)
10a Four-point contact ball bearing (rolling bearing for drive unit)
11 outer ring 12 inner ring 15 cylindrical roller (rolling element)
17 ball 20 cage 21a guide surface 23 concave groove

Claims (2)

A drive having an outer ring, an inner ring, a plurality of rolling elements that are rotatably arranged between the raceways of the outer ring and the inner ring, and a cage that holds the plurality of rolling elements at predetermined intervals in the circumferential direction. It is a rolling bearing for an apparatus, and the cage is an outer ring guide system, and includes a pair of guide surfaces guided to the inner peripheral surface of the outer ring on both sides in the axial direction. A plurality of grooves formed at equal intervals in the circumferential direction in the same number as the rolling elements and positioned in the same phase on both sides in the axial direction. Each of the concave grooves is formed so that a circumferential intermediate portion thereof coincides with a circumferential phase of the center of the rolling element. The depth of each concave groove is 16 to 22% of the radial thickness of the cage, and an angle θ connecting the circumferential ends of the concave grooves from the center of the cage is 360 ° / ( 2.5 × number of rolling elements) ≦ θ ≦ 360 ° / (2 × number of rolling elements), and the groove cross-sectional area × the number of rolling elements = 1.5 to 3.6 × guide clearance cross-sectional area. The rolling bearing for a driving device according to claim 1.

Images