Cam shaft support structure and internal combustion engine

摘要

A needle roller bearing (21) as a roller bearing comprises an outer ring (22) formed by connecting a plurality of arc-shaped outer ring members in a circumferential direction, and a plurality of needle rollers (23) arranged along the inner diameter surface of the outer ring (22), and an oil groove (22i) extending in a circumferential direction so as to contain a position opposed to an opening (13e) of an oil path of a housing is formed in the outer diameter surface of the outer ring member.