Sheet post-processing apparatus and image forming apparatus

The sheet post-processing apparatus, comprising:

• a conveyance portion configured to convey a sheet;
• a transport portion configured to abut on a lower surface of the sheet conveyed by the conveyance portion, to transport the sheet downstream in a sheet conveyance direction of the conveyance portion;
• a pressing portion arranged at a position opposing the transport portion, configured to press an upper surface of the sheet conveyed by the conveyance portion;
• a moving portion configured to move the pressing portion in the sheet conveyance direction of the conveyance portion and in a direction opposite to the sheet conveyance direction;
• and
• a controller configured to control the transport portion, so that the moving portion moves the pressing portion in the opposite direction from a first position where a preceding sheet is pressed to a second position, disposed upstream of the first position in the sheet conveyance direction, to press a succeeding sheet conveyed by the conveyance portion, and
• so that the transport portion transports the preceding sheet and the succeeding sheet in the sheet conveyance direction while the pressing portion presses the succeeding sheet whose downstream end portion in the sheet conveyance direction overlapping with an upstream end portion of the preceding sheet.

An image forming apparatus comprising:

• an image forming portion configured to form an image on a sheet;
• and
• a sheet post-processing apparatus for post-processing the sheet having the image formed thereon comprising:
• a conveyance portion configured to convey a sheet having a folded end portion;
• a transport portion configured to abut on a lower surface of the sheet conveyed by the conveyance portion, to transport the sheet downstream in a sheet conveyance direction of the conveyance portion;
• a pressing portion arranged at a position opposing the transport portion, configured to press an upper surface of the sheet conveyed by the conveyance portion;
• a moving portion configured to move the pressing portion in the sheet conveyance direction of the conveyance portion and in a direction opposite to the sheet conveyance direction;
• and
• a controller configured to control the moving portion, so that the moving portion moves the pressing portion in the opposite direction from a first position to a second position, disposed upstream of the first position in the sheet conveyance direction, to press the sheet conveyed by the conveyance portion, and
• so that the moving portion moves the pressing portion in the sheet conveyance direction from the second position to the first position while the pressing portion presses the sheet being transported by the transport portion.

An image forming apparatus comprising:

• an image forming portion configured to form an image on a sheet;
• and
• a sheet post-processing apparatus for post-processing the sheet having the image formed thereon comprising:
• a conveyance portion configured to convey a sheet having a folded end portion;
• a transport portion configured to abut on a lower surface of the sheet conveyed by the conveyance portion, to transport the sheet downstream in a sheet conveyance direction of the conveyance portion;
• a pressing portion arranged at a position opposing the transport portion, configured to press an upper surface of the sheet conveyed by the conveyance portion;
• a moving portion configured to move the pressing portion in the sheet conveyance direction of the conveyance portion and in a direction opposite to the sheet conveyance direction;
• and
• a controller configured to control the moving portion, so that the moving portion moves the pressing portion in the opposite direction from a first position where a preceding sheet is pressed to a second position, disposed upstream of the first position in the sheet conveyance direction, to press a succeeding sheet conveyed by the conveyance portion, and
• so that the transport portion transports the preceding sheet and the succeeding sheet in the sheet conveyance direction while the pressing portion presses the succeeding sheet whose downstream end portion in the sheet conveyance direction overlapping with an upstream end portion of the preceding sheet.