Sheet feeding device and image forming apparatus

A sheet feeding device, comprising:

• a sheet feeding unit configured to feed a sheet;
• a sheet containing unit configured to contain the sheet;
• a sheet stacking unit configured to stack the sheet and provided in the sheet containing unit so as to be capable of being raised and lowered;
• a pair of side edge regulating portions provided to be opposed to each other in the sheet containing unit so as to regulate side edge positions of the stacked sheet in a width direction orthogonal to a sheet feeding direction, at least one of the pair of side edge regulating portions being movable in the width direction;
• auxiliary side edge regulating portions provided downstream of the pair of side edge regulating portions in the sheet feeding direction so as to be moved with the pair of side edge regulating portions in the width direction, and configured to form flush surfaces along the sheet feeding direction together with the pair of side edge regulating portions so as to regulate the side edge positions of the stacked sheet at retreat positions, the auxiliary side edge regulating portions being movable to the retreat positions and protruding positions, at which the auxiliary side edge regulating portions protrude in the width direction with respect to the pair of side edge regulating portions;
• and
• support units configured to support the auxiliary side edge regulating portions so that abutment surfaces of the auxiliary side edge regulating portions, which abut against the sheet, are movable in the width direction with respect to the pair of side edge regulating portions in a state of being parallel to the sheet feeding direction,
• wherein a distance between the abutment surfaces of the auxiliary side edge regulating portions at the protruding positions is narrower than a distance between the pair of side edge regulating portions in a state in which movement of the pair of side edge regulating portions in the width direction is regulated by the sheet stacking unit.