JP-2026075473-A - Bearing washers

Abstract

[Problem] To provide a bearing washer having a recess for retaining lubricant without degrading sliding performance. [Solution] A bearing washer 1 is sandwiched between two relative rotating members and slides against at least one of the members, and has a recess 6 formed on the sliding surface that contacts the members, wherein the sliding surface has broken edge portions 9, 9i, 9o, and the recess 6 is formed in a predetermined area at a predetermined distance L from the edge portions 9, 9i, 9o and has a closed contour shape. Therefore, it is possible to avoid the recess 6's contour being chipped and burrs being generated in that portion, and to obtain a washer 1 that does not hinder sliding performance such as catching on the mating member. [Selection Diagram] Figure 4

Inventors

• 荒田 康太朗
• 戸成 康宏
• 羽畑 元貴

Assignees

• トヨタ自動車株式会社
• 日本発條株式会社

Dates

Publication Date

20260508

Application Date

20241022

Claims (2)

1. A bearing washer that is sandwiched between two relative rotating members, slides against at least one of the members, and has a recess formed on the sliding surface that contacts the member, The sliding surface has an edge portion that is interrupted, The bearing washer is characterized in that the recess is formed within a predetermined area a predetermined distance from the edge and has a closed contour shape.
2. A bearing washer according to claim 1, The bearing washer is characterized in that the region is limited to the region that contacts one of the members.

Description

This invention relates to a washer inserted between two members for purposes such as protecting the contact surface and improving adhesion. In particular, it relates to a washer for a bearing, which is inserted between two relatively rotating members and subjected to a thrust load. Metal components that rotate relative to each other in surface contact face problems such as increased frictional resistance and reduced durability due to wear if the metal base materials are in direct contact. Therefore, it is common practice to use a lubricant. While lubricating oil is widely used as a lubricant, it can be difficult to supply sufficient lubricant to the friction surface. For this reason, methods for retaining lubricating oil on the friction surface have been conventionally employed. Examples of this are described in Patent Documents 1 to 3. Patent Document 1 describes a washer that receives a thrust load. This washer comprises a base material having a thrust surface that receives the thrust load, and a coating layer formed on at least a portion of the thrust surface. The coating layer comprises a binder resin and a solid lubricant dispersed in the binder resin, with an exposure rate of 7% or more of the solid lubricant on the sliding surface of the coating layer. Furthermore, the thrust surface has oil grooves for retaining lubricating oil, and the coating layer is not formed in these oil grooves. For example, these oil grooves are formed to traverse the surface of the base material, which is curved in an arc, in the radial direction, reaching both the outer and inner circumferences of the arc, and are open. Furthermore, Patent Document 2 discloses a sliding member made of sintered metal, in which multiple dimples are provided on the bearing surface as recesses for retaining lubricating oil. Patent Document 3 describes a structure that improves the lubricity of relatively sliding discs. Patent Document 3 describes an impact absorbing device in which a fixed disc and a rotating disc are brought into contact by elastic force, and when a torque exceeding the frictional force between these discs is applied, slippage occurs between the discs. Multiple dimples are formed on the friction surfaces of these discs as recesses for retaining lubricant. These dimples are formed, for example, by punching. In this case, the material flowing around the punch causes bulges, forming protrusions around the dimples. Japanese Patent Publication No. 2018-035838Japanese Patent Publication No. 2008-248975Japanese Patent Publication No. 2008-116038 This is a cross-sectional view showing one embodiment of the present invention, illustrating the state in which it is used in a differential gear.This is a plan view of the washer.This is a cross-sectional view showing a portion of the washer.This is a plan view showing a portion of the washer used to explain the area where the dimples are to be made.This is a schematic partial perspective view showing an example of burrs forming on a conventional washer.This is a schematic cross-sectional view showing an example where part of the surface or back surface of a washer is detached from the mating component and does not form a sliding surface.This is a model diagram illustrating the formula for defining the limit position of the area where elliptical or oval-shaped dimples are to be made. Next, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the embodiments described below are merely examples of how the present invention can be implemented and do not limit the invention. The washer according to the present invention is a metal plate that is sandwiched between two relative rotating members to allow them to operate smoothly and to suppress friction and wear. A specific example is shown in Figure 1, where the washer 1 is a washer provided on a differential gear and functions as a bearing. As is conventionally known, a differential gear has a pinion 3 positioned between left and right side gears 2a and 2b. The pinion 3 revolves around the central axis of the side gears 2a and 2b, transmitting torque to the side gears 2a and 2b, and the pinion 3 rotates on its own axis, causing differential rotation of the left and right side gears 2a and 2b. The pinion 3 is rotatably fitted onto a pinion shaft 4 that passes through it along its central axis, and the pinion shaft 4 is held in the differential case 5. Therefore, the rotation of the differential case 5 causes the pinion 3 to revolve. The side gears 2a, 2b and pinion 3 are bevel gears, and therefore, the transmission of torque between them generates a thrust force that pushes pinion 3 toward the inner surface of the differential case 5. In this embodiment of the present invention, the washer 1 is positioned between pinion 3 and differential case 5, where this thrust force acts. Figure 1 shows the cross-sectional shape of washer 1, and Figure 2 shows its shape when viewed from the front. Since