METHOD FOR DESIGNING THRUST NEEDLE BEARING, THRUST NEEDLE BEARING, AND METHOD FOR MANUFACTURING THRUST NEEDLE BEARING

摘要

In order to provide a thrust needle bearing that is extremely quiet and has a lower cost than a conventional thrust needle bearing, this method for designing a thrust needle bearing used in an automatic transmission is equipped with: a step in which multiple thrust needle bearings each having a different first length (L1) in a second direction at a back surface (12) are prepared, and an acoustic characteristic of the multiple prepared thrust needle bearings (100) is checked; and a step in which a design value for the first length (L1) is determined such that the acoustic characteristic is within a permissible range.