Sheet processing device

An image forming apparatus, comprising:

• an image forming component;
• and
• a sheet processing device, comprising:
• a processing section configured to process a sheet;
• a tray on a first surface on a first side of which the sheet is placed;
• a lifting and lowering device configured to move the sheet to the processing section;
• a single flexible member having flexibility and provided on the first side of the tray;
• a first member connected to a first end portion of the single flexible member;
• a second member connected to a second end portion opposite to the first end portion of the single flexible member and separated from the first member in a first direction, a separation distance between the second member and the first member being shorter than length of the single flexible member between the second member and the first member;
• a driving source configured to cause the second member to operate;
• and
• a controller configured to control operation of the driving source.