Sheet feeder and image forming apparatus

An image forming apparatus comprising:

• a sheet feeder;
• and
• a print engine configured to print an image on a sheet fed by the sheet feeder,
• the sheet feeder comprising:
• a separation roller configured to feed a sheet in a feed direction;
• a separation pad facing the separation roller;
• a spring configured to exert an urging force that presses the separation pad toward the separation roller;
• an actuator configured to detect the sheet that is fed, the actuator including a rotation shaft and a contact piece, the rotation shaft having one end and an other end in a width direction perpendicular to the feed direction, the rotation shaft being rotatable about a rotation axis extending in the width direction, the contact piece being configured to contact the sheet and to rotate about the rotation axis together with the rotation shaft;
• and
• a frame configured to support the separation pad to contact and separate from the separation roller, the frame rotatably supporting the one end and the other end of the rotation shaft,
• the spring being located between the separation pad and the frame,
• the frame being configured to receive a downward reaction force that is a reaction force of the urging force,
• the rotation shaft and the contact piece being located at one side of the separation pad in the width direction,
• the frame having an upper edge in a first region defined between the one end and the other end of the rotation shaft in the width direction, a height of the upper edge in the first region being at a same height or below the rotation axis,
• the frame including a standing wall in a second region in the width direction, the standing wall extending farther upward than the upper edge in the first region, the second region including a region in which the separation pad is located, the second region being other than the first region.