Sheet discharging apparatus and image forming apparatus

A sheet discharging apparatus comprising:

• a sheet discharging apparatus main body portion;
• a plurality of discharging rollers, attached to the apparatus main body portion, which discharge sheets, onto a catch tray, through a rotation thereof;
• a shaft which is coaxially fixed to the plurality of the discharging rollers, wherein the shaft has first diameter portions and at least one second diameter portion disposed adjacent to a discharging roller, wherein the first diameter portions have a first diameter smaller than a diameter of the plurality of discharging rollers, and the at least one second diameter portion has a second diameter smaller than the first diameter;
• and
• a projection, which projects from the apparatus main body portion, comprising a tip end disposed in a groove formed by the at least one second diameter portion;
• wherein the shaft rotates in a direction such that, at a side adjacent to the catch tray, the shaft rotates downward toward an upper surface of the catch tray.