| 摘要 |
A needle roller bearing comprises a plurality of needle rollers and a retainer. The retainer includes a pair of annular parts and pillar parts connecting the pair of annular parts so as to form pockets in which the needle rollers are housed. A sidewall surface of the pillar part has a sheared surface punched by a punching blade so that the pockets are formed, and a fractured surface fractured by a material pressed by the punching blade. The needle roller is guided by the sheared surface.
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