Sheet feeding apparatus and image forming apparatus

摘要

A sheet feeding roller 101 which feeds a sheet S stacked on a sheet supporting plate 110 capable of being lifted and lowered is swingably supported at a swing end of a sheet feeding roller supporting arm 104 which is arranged swingably in an up-and-down direction and a roller biasing member applies a force to the sheet feeding roller supporting arm in a direction that the sheet feeding roller is pressed to sheets S stacked on a sheet stack tray. A swing fulcrum 104a is arranged in a range between a tangential line of the sheet feeding roller at the upstreammost pressing position against the sheet feeding direction and a tangential line of the sheet feeding roller at the downstreammost pressing position out of pressing positions where the sheet feeding roller is pressed to the sheets as being varied in accordance with a sheet stacking state of the sheets.

主权项

1. A sheet feeding apparatus, comprising:
a sheet storage portion which includes a sheet stack tray which is swingable in an up-and-down direction; a feeding roller which is arranged above the sheet stack tray and which feeds an uppermost sheet stacked on the sheet stack tray; a support member which is swingable in an up-and-down direction about a swing fulcrum and which supports the feeding roller to be swingable at a swing end; and a roller biasing member which applies a force to the support member in a direction in which the feeding roller is pressed to the uppermost sheet stacked on the sheet stack tray; and a separation roller, disposed downstream of the sheet stack tray in a sheet feeding direction, which is pressed against feeding roller to form a separation portion with the feeding roller that separates the sheets.