Sheet feeding apparatus and image forming apparatus

摘要

A sheet feeding apparatus has three sheet feeding units stacked vertically and is detachably mounted to an image forming apparatus. The upper most sheet feeding unit includes a tray for stacking and storing a sheet; a pick-up roller for feeding the sheet one at a time; a feed roller; a retard roller; a pair of register rollers; a curl forming portion for abutting against a leading edge of the sheet fed by these rollers in the sheet feeding direction to remove skew of the sheet by curling the sheet and for allowing the sheet to move further downstream; and a cylindrical cutter for punching a hole in the sheet. The sheet is transferred in a short distance and the sheet is fed one at a time.