JP-2026074702-A - Angular contact ball bearing and method for manufacturing the same

Abstract

[Problem] To provide an angular contact ball bearing and a method for manufacturing the same, which allows for weight reduction by using press-formed steel plates for the outer and inner rings, prevents the outer or inner ring from separating from the balls, provides good handling, and ensures sealing performance. [Solution] In the angular contact ball bearing 10, the outer ring 21 and the inner ring 22 are press-formed products of steel plate, and at least one of the outer ring 21 and the inner ring 22 has engagement portions 20 and 30. Furthermore, the inner ring 22 has an inner ring extension portion 32 that extends outward from the side opposite to the cylindrical portion 28 of the spherical annular portion 26 and forms a labyrinth seal with the outer ring 21. [Selection Diagram] Figure 1

Inventors

• 浜崎 紘至
• 齋藤 智治
• 松崎 遥

Assignees

• 日本精工株式会社

Dates

Publication Date

20260507

Application Date

20241021

Claims (6)

1. The device comprises an outer ring having an outer ring raceway surface on its inner circumference, an inner ring having an inner ring raceway surface on its outer circumference, and a plurality of balls arranged to roll freely between the outer ring raceway surface and the inner ring raceway surface with a contact angle between them. The angular contact ball bearing is made of a press-formed steel plate, and the outer ring and inner ring are press-formed steel plates. The outer ring and the inner ring each comprise a spherical annular portion with a circular arc cross-section that forms the outer ring raceway surface or the inner ring raceway surface, and a cylindrical portion that extends axially from the spherical annular portion on the side opposite to the outer ring raceway surface or the inner ring raceway surface with respect to the center of the ball. At least one of the outer ring and the inner ring is located radially closer to the center of the ball than the deepest part of the outer ring raceway surface or the inner ring raceway surface, and has an overlapping portion that overlaps with the ball when viewed from the axial direction. The inner ring has an inner ring extension that extends from the side of the spherical annular portion opposite to the cylindrical portion toward the outer diameter, and has an inner ring extension that forms a constricted portion between it and the outer ring. Angular contact ball bearing.
2. The outer ring extends radially outward from the cylindrical portion and has a flange portion that forms the constricted portion between it and the inner ring extension. The angular contact ball bearing according to claim 1.
3. The device further comprises a holder that holds the plurality of balls at predetermined intervals in the circumferential direction. The angular contact ball bearing according to claim 1.
4. The constricted portion forms a non-contact seal. The angular contact ball bearing according to claim 1.
5. It is for motor support. The angular contact ball bearing according to claim 1.
6. A method for manufacturing an angular contact ball bearing according to any one of claims 1 to 5, The steps include at least heating the outer ring having the aforementioned overlapping portion, A step of assembling a plurality of balls by shrink-fitting between the outer ring raceway surface of the heated outer ring and the inner ring raceway surface of the inner ring having the engagement portion, Equipped with, A method for manufacturing angular contact ball bearings.

Description

This invention relates to an angular contact ball bearing and a method for manufacturing the same, and more particularly to an angular contact ball bearing in which the outer ring and inner ring are formed by press working, and a method for manufacturing the same. In recent years, weight reduction has become a crucial issue in the automotive and aerospace industries, leading to a demand for lightweight yet high-performance angular contact ball bearings incorporated into these products. Angular contact ball bearings are known to be manufactured by press-forming metal plates to produce each raceway ring (outer ring and inner ring) (see, for example, Patent Documents 1 to 3). For example, in the small press bearing described in Patent Document 1, the inner ring is formed from a cylindrical member having recesses that support a large number of balls in the circumferential direction of the outer surface, and the outer ring is formed from a press-formed product made from a single member. The outer ring is provided with a contact portion having a projection that contacts each ball from the radially outward side of the bearing and prevents the ball from moving in one axial direction of the bearing, and an inner end portion that extends radially inward from the other axial direction and ends leaving a small gap between it and the outer circumference of the inner ring. Japanese Patent Application Publication No. 7-224840Japanese Patent Publication No. 2019-39492Japanese Patent Publication No. 2015-14367 This is a cross-sectional view of a bearing device to which an angular contact ball bearing according to one embodiment of the present invention is applied.Figure 2(a) is a cross-sectional view of the outer and inner rings, and Figure 2(b) is an enlarged cross-sectional view of (a). The angular contact ball bearing and bearing device according to one embodiment of the present invention will be described in detail below with reference to the drawings. As shown in Figure 1, the bearing device 1 of this embodiment is a bearing device for a drone propeller motor. The motor 6 is composed of a stator 3 fitted onto a housing 2 and a rotor 5 fixed to a rotating shaft 4. The rotating shaft 4 is rotationally driven relative to the housing 2 via two angular contact ball bearings 10 and 11. In this embodiment, the housing 2 is made of aluminum, and the rotating shaft 4 is made of SUJ2 steel. Referring also to Figure 2, the two angular contact ball bearings 10 and 11 are fitted in the housing 2 via an intermediate fit and each comprises outer rings 21 and 22 having outer ring raceway surfaces 21a and 22a on their inner circumferential surfaces, inner rings 23 and 24 fitted in an intermediate fit on the rotating shaft 4 and having inner ring raceway surfaces 23a and 24a on their outer circumferential surfaces, and a plurality of balls 41 and 42 arranged to roll freely between the outer ring raceway surfaces 21a and 22a and the inner ring raceway surfaces 23a and 24a with a contact angle α. In this embodiment, the contact angle α is set to 25 to 40°. In Figure 1, a spacer 50 made of SUJ2 is positioned between the outer rings 21 and 22 of the two angular contact ball bearings 10 and 11. Furthermore, a retaining element 51 is provided at the lower end of the rotating shaft 4 to prevent the inner ring 24 of the lower angular contact ball bearing 11 from falling out. The two angular contact ball bearings 10 and 11 are arranged in a back-to-back (DB) configuration, and a preload is applied. The outer rings 21, 22 and inner rings 23, 24 are press-formed products of steel sheet such as SK85, and each comprises a spherical annular portion 25, 26 with a circular arc cross-section that forms the outer ring raceway surfaces 21a, 22a or the inner ring raceway surfaces 23a, 24a, and cylindrical portions 27, 28 that extend axially from the spherical annular portions 25, 26 on the side opposite to the outer ring raceway surfaces 21a, 22a or the inner ring raceway surfaces 23a, 24a with respect to the center O of the balls 41, 42. The boundary portion of the cylindrical portion 27 of the outer rings 21 and 22 with the spherical annular portion 25 is formed by partially grinding or barrel finishing the inner circumferential surface of the cylindrical portion 27 so that it becomes the deepest part of the outer ring raceway surfaces 21a and 22a. Similarly, the boundary portion of the cylindrical portion 28 of the inner rings 23 and 24 with the spherical annular portion 26 is formed by partially grinding or barrel finishing the outer circumferential surface of the cylindrical portion 28 so that it becomes the deepest part of the inner ring raceway surfaces 23a and 24a. Therefore, the outer rings 21, 22 and inner rings 23, 24 are positioned radially closer to the center of the balls 41, 42 by an overlapping portion a than the deepest part of the outer ring raceway surfaces 21a, 22a and inner ring raceway surfaces 23a, 24a, and have overlapping portions