Bearing structure for rotatable shaft

摘要

A bearing structure has first and second support members in which first and second stepped small-diameter portions of drive and nip rollers are rotatably mounted by bearings. The first and second support members are disposed in respective first and second holes defined in a side wall and have respective first and second inner engaging teeth and respective first and second outer engaging flanges which are held against respective opposite surfaces of the side wall to retain the first and second support members on the side wall against removal. The first and second support members thus firmly retained in position on the side wall can reliably bear thrust forces from the drive roller and the nip roller. The drive roller and the nip roller and the bearings can be assembled and serviced with ease. First and second snap-fitting gears mounted on the first and second stepped small-diameter portions adjacent to the first and second support members, respectively, are effectively protected against damage because thrust forces from the drive roller and the nip roller are borne by the first and second support members.