IMAGE FORMING APPARATUS

摘要

An image forming apparatus includes an image forming unit configured to form an image on a sheet, a stacking portion on which the sheet having the image formed thereon is to be stacked, a first roller capable of forward and reverse rotations, a second roller capable of rotating with the first roller when the first roller makes a forward rotation, a third roller capable of rotating with the first roller when the first roller makes a reverse rotation and then the forward rotation, a regulation portion movable between a regulation position where entering of the sheet into a nip portion between the first and second rollers is prevented, and an allowing position where discharge of the sheet is allowed, and a movement unit configured to cause the regulation portion to be placed in the allowing position during forward rotation, and to be placed in the regulation position during reverse rotation.

主权项

1. An image forming apparatus comprising:
an image forming unit configured to form an image on a sheet; a stacking portion on which the sheet having the image formed thereon by the image forming unit is to be stacked; a first roller configured to be capable of forward rotation and reverse rotation; a second roller which has a rotation center disposed below a rotation center of the first roller in a vertical direction in normal operation, and which is configured to rotate with the first roller when the first roller makes a forward rotation when the sheet is to be discharged onto the stacking portion; a third roller which has a rotation center disposed above the rotation center of the first roller in the vertical direction in normal operation, and which is configured to rotate with the first roller when the first roller makes a reverse rotation and then the forward rotation when a sheet having an image formed on a first side thereof by the image forming unit is to be conveyed to the image forming unit to form an image on a second side thereof opposite to the first side; a regulation portion provided so as to be movable between a regulation position where entering of the sheet stacked on the stacking portion into a nip portion between the first roller and the second roller is prevented, and an allowing position where discharge of the sheet by the first roller and the second roller is allowed; and a movement unit configured to cause the regulation portion to be placed in the allowing position while the first roller performs a forward rotation, and to cause the regulation portion to be placed in the regulation position while the first roller performs a reverse rotation.