| 摘要 |
PROBLEM TO BE SOLVED: To form a retainer 10b that is incorporated into a thrust roller bearing for a power roller and has protrusions 15a, 15a on both sides of respective pillar parts 13b, 13b by injection molding of a synthetic resin, thereby suppressing formation of a detrimental recess on a surface of the retainer 10b based on a molding sink after injection molding.SOLUTION: In respective pillar parts 13b, 13b, cavities 16, 16 are provided which are opened on a front end surface of the respective pillar parts 13b, 13b and reach to a part superimposed on the respective protrusions 15a, 15a regarding the axial direction of the retainer 10b. With this configuration, the wall thickness of the respective pillar parts 13b, 13b provided with the respective protrusions 15a, 15a is reduced, and the occurrence of a recess based on the molding sink is suppressed. |
