| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a needle roller bearing with high reliability even while using a resin material. <P>SOLUTION: When a groove 52d is provided on an outer periphery of an annular part 52a, lubricating oil tends to accumulate in the groove 52d, oil film formation on a guide face is promoted by the lubricating oil, and a cooling effect of a heat generation part can be obtained. Further, by providing the groove 52d, the contact area between the annular part 52a and the outside air is increased, and a heat radiation effect can be expected. The radial needle roller bearing capable of responding to high speed rotation while reducing drag torque using a resin material can be provided by adopting a countermeasure against such heat generation. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
