Ball bearing

Abstract

A ball bearing is described, which comprises an outer ring having on its inner periphery an outer raceway, an inner ring having on its outer periphery an inner raceway, plural balls rotatably disposed between the outer raceway and the inner raceway, a cage holding the plural balls in a freely rotatable manner, and a grease packed in a space between the outer raceway and the inner raceway, wherein the inner peripheral surface of each pocket of the cage contains a spherical part consisting of a spherical concave surface whose radius of curvature is slightly larger than that of each ball and a curved part which has the radius of curvature being larger than that of the spherical part and is smoothly continuous from the end of the spherical part toward the end thereof on the opening side of the pocket.

Description

technical field [0001] The present invention relates to ball bearings for various types of motors used in general industries, and more particularly to ball bearings intended to reduce retainer noise, reduce vibration, improve fretting wear (abrasion), achieve low torque, and improve noise durability. Background technique [0002] For general industrial use, for example, an air-conditioning device (hereinafter referred to as "air conditioner") driving motor device is mentioned. In recent years, with the development of high performance and multi-functionality of this air conditioner, the following technology has been developed, that is, using, for example, frequency conversion control, through high-speed operation to quickly cool down the indoor temperature in a short time, and then to lower the room temperature by low-speed operation. Maintain a certain amount. For this reason, low-noise operation that can suppress the exhaust sound of the air and the rotation sound of the m...

AI Technical Summary

Problems solved by technology

On the opposite side of the retainer 6 in the circumferential direction, a portion of the rolling surface of the ball 5 that is close to the inner diameter of the retainer 6 and a portion of the spherical portion 15 that constitutes the inner peripheral surface of the cavity 7 that is close to the inner diameter of the retainer 6 occur in sliding contact. Phenomenon, poor lubricant uptake still occurs

[0018] As a result of such poor lubricant intake, the friction coefficient of the sliding joint between the rolling surface of each ball 5 and the spherical portion 15 constituting the inner peripheral surface of the cavity 7 of the retainer 6 increases.

As a result, there will be problems such as fluctuation or increase of the frictional torque of the ball bearing assembled with the retainer 6, frictional noise during operation, or obvious frictional noise under certain circumstances.

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