Sheet feeding device and image forming apparatus

An image forming apparatus comprising:

• a raising and lowering portion for raising and lowering a stacking member for stacking a sheet;
• a first detecting portion for detecting whether or not an uppermost sheet stacked on said stacking member raised by said raising and lowering portion is in a feeding position;
• a feeding portion for feeding the uppermost sheet by causing a feeding roller to press contact the uppermost sheet;
• a second detecting portion for detecting whether or not the feeding roller is in a position where the feeding roller is capable of feeding the uppermost sheet;
• and
• a controller for controlling said raising and lowering portion,
• wherein said raising and lowering portion raises said stacking member and detection that the uppermost sheet is in the feeding position is made by said first detecting portion, and thereafter said feeding portion causes the feeding roller to press contact the uppermost sheet, and
• wherein when a change in a state of the feeding roller from a state in which the feeding roller is in the position where the feeding roller is capable of feeding the uppermost sheet to a state in which the feeding roller is not in the position where the feeding roller is capable of feeding the uppermost sheet is detected by said second detecting portion and then a change in a state of the uppermost sheet from a state in which the uppermost sheet is in the feeding position to a state in which the uppermost sheet is not in the feeding position is detected by said first detecting portion, said controller determines a correction amount on the basis of a time from change timing of said second detecting portion to change timing of said first detecting portion and controls said raising and lowering portion to raise said stacking member on the basis of the correction amount.