| 释义 |
ball bearing
noun
1.
a. : a bearing in which the journal turns upon loose hardened steel balls that roll easily in a race and thus convert sliding friction into rolling friction
b. : any of the balls in such a bearing
2. : a bearing in which the disk of a watt-hour meter is mounted on a vertical shaft that rotates with minimized friction because of rolling action on a single steel ball between cupped jewels |