Rolling bearing and spindle apparatus for machine tool

    公开(公告)号:USRE48843E1

    公开(公告)日:2021-12-07

    申请号:US16381315

    申请日:2019-04-11

    Applicant: NSK LTD.

    Abstract: A rolling bearing includes an inner ring having an outer surface, an outer ring having an inner surface, a plurality of rolling elements rotatably disposed between the inner ring and the outer ring, and a retainer for retaining the rolling elements. The retainer is made of a resin material and is positioned with respect to the inner surface of the outer ring or the outer surface of the inner ring. The retainer includes a pair of annular portions axially arranged in parallel and a columnar portion coupling the annular portions. Then, the rolling bearing satisfies the following expression: AI=LH3/dm≥0.025 LH3/dm2≥0.025 mm2 in which H is a radial length of a section of the annular portion, L is an axial length of the same, and dm is PCD of the rolling element.

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