Sheet feeding apparatus and image forming system

A sheet feeding apparatus comprising:

• a sheet supporting portion configured to support sheets;
• a first suction portion configured to attract, by suction, an uppermost sheet of the sheets supported on the sheet supporting portion;
• a first blowing portion configured to blow air onto the sheets supported on the sheet supporting portion from a downstream side toward an upstream side in a sheet feeding direction;
• and
• a controller capable of executing a first mode in which a sheet of a first type supported on the supporting portion is fed and a second mode in which a sheet of a second type supported on the sheet supporting portion is fed, the second type having a higher rigidity than the first type,
• wherein the controller is configured to:
• in the first mode, start the suction of the uppermost sheet by the first suction portion after starting blowing of the air by the first blowing portion;
• and
• in the second mode, start the suction of the uppermost sheet by the first suction portion before starting the blowing of the air by the first blowing portion.

A sheet feeding apparatus comprising:

• a sheet supporting portion configured to support sheets;
• a first suction portion configured to attract, by suction, an uppermost sheet of the sheets supported on the sheet supporting portion;
• a second suction portion disposed at a position upstream of the first suction portion in a sheet feeding direction and configured to attract, by suction, the uppermost sheet of the sheets supported on the sheet supporting portion;
• a first blowing portion configured to blow air onto the sheets supported on the sheet supporting portion from a downstream side toward an upstream side in the sheet feeding direction;
• and
• a controller capable of executing a third mode in which a sheet of a third type supported on the supporting portion is fed and a fourth mode in which a sheet of a fourth type supported on the sheet supporting portion is fed, sheets of the fourth type sticking more strongly to each other than sheets of the third type,
• wherein the controller is configured to:
• in the third mode, start the suction of the uppermost sheet by the second suction portion after starting blowing of the air by the first blowing portion;
• and
• in the fourth mode, start the suction of the uppermost sheet by the second suction portion before starting the blowing of the air by the first blowing portion.