The present invention provides a sheet stacking device, a counter-ejector, and a carton former and is provided with: a hopper unit that stacks cardboard boxes; feed rollers that feed a cardboard box to the hopper unit; a first blower device that blows air from above the hopper unit toward the cardboard box fed by the feed rollers; and a second blower device that blows air between the cardboard box stacked in the hopper unit and the cardboard box fed by the feed roller.

An image forming apparatus includes a processing tray, a post-processing controller, and a detection sensor. The processing tray is configured to support a sheet or a sheet bundle on which a post-processing is to be executed. The post-processing controller is configured to execute the post-processing on the sheet positioned on the processing tray. The detection sensor is configured to detect an object in a predetermined detection range including a space above the processing tray. The post-processing controller stops execution of the post-processing when the detection sensor detects the object at a determination timing other than a timing at which passage of the sheet or the sheet bundle through the detection range is estimated.

An image forming apparatus includes a processing tray, a post-processing controller, and a detection sensor. The processing tray is configured to support a sheet or a sheet bundle on which a post-processing is to be executed. The post-processing controller is configured to execute the post-processing on the sheet positioned on the processing tray. The detection sensor is configured to detect an object in a predetermined detection range including a space above the processing tray. The post-processing controller stops execution of the post-processing when the detection sensor detects the object at a determination timing other than a timing at which passage of the sheet or the sheet bundle through the detection range is estimated.

A sheet post processing device includes a loading tray on which a sheet conveyed thereto is loaded, a side end edge binding stapler fixed at a position opposed to a side end edge, along a conveyance direction, of a sheet bundle of a plurality of sheets loaded on the loading tray, the side end edge binding stapler performing a first binding process on the side end edge, a conveyance unit that moves the sheet bundle on the loading tray in the conveyance direction, and a controller that controls the conveyance unit. The controller can cause the conveyance unit to move the sheet bundle in the conveyance direction so as to perform the first binding process on the sheet bundle with the side end edge binding stapler at a plurality of positions along the side end edge.

A sheet post processing device includes a loading tray on which a sheet conveyed thereto is loaded, a side end edge binding stapler fixed at a position opposed to a side end edge, along a conveyance direction, of a sheet bundle of a plurality of sheets loaded on the loading tray, the side end edge binding stapler performing a first binding process on the side end edge, a conveyance unit that moves the sheet bundle on the loading tray in the conveyance direction, and a controller that controls the conveyance unit. The controller can cause the conveyance unit to move the sheet bundle in the conveyance direction so as to perform the first binding process on the sheet bundle with the side end edge binding stapler at a plurality of positions along the side end edge.

Post-processing apparatus for performing given process subsequently to image forming process by image forming apparatus is disclosed. Post-processing apparatus includes: first ejector which ejects sheet; first tray which temporarily holds sheet; second tray situated downstream of first tray in ejection direction of sheet; a tray driver which moves second tray downwardly from first height position; blower which forms airstream between second tray and lower surface of sheet; and controller which controls blower and tray driver. Controller includes: blower controller which causes blower to blow air over time period in synchronization with first time period from start to end of sheet ejection by first ejector; and tray controller which causes tray driver to move second tray downwardly from first height position after first time period.

Post-processing apparatus for performing given process subsequently to image forming process by image forming apparatus is disclosed. Post-processing apparatus includes: first ejector which ejects sheet; first tray which temporarily holds sheet; second tray situated downstream of first tray in ejection direction of sheet; a tray driver which moves second tray downwardly from first height position; blower which forms airstream between second tray and lower surface of sheet; and controller which controls blower and tray driver. Controller includes: blower controller which causes blower to blow air over time period in synchronization with first time period from start to end of sheet ejection by first ejector; and tray controller which causes tray driver to move second tray downwardly from first height position after first time period.

A sheet processing apparatus includes a roller pair configured to convey a sheet, a sheet bundle conveyer configured to convey a sheet bundle to the roller pair, and circuitry configured to cause the sheet bundle conveyer to contact leading edges of sheets of the sheet bundle to the roller pair and cause the roller pair to rotate in reverse to align the leading edges of the sheets of the sheet bundle.

A sheet stacking apparatus includes a sheet alignment mechanism configured for aligning a sheet in a predetermined reference position; a gripper arrangement configured to grip the aligned sheet at at least two spaced-apart points of the sheet and to release the sheet on a stack; and a holder configured to hold the sheet in position on the stack while the gripper arrangement releases the sheet. The gripper arrangement is movable along a predetermined trajectory for moving the sheet from the reference position to a stacking position.

A sheet stacking apparatus includes a sheet alignment mechanism configured for aligning a sheet in a predetermined reference position; a gripper arrangement configured to grip the aligned sheet at at least two spaced-apart points of the sheet and to release the sheet on a stack; and a holder configured to hold the sheet in position on the stack while the gripper arrangement releases the sheet. The gripper arrangement is movable along a predetermined trajectory for moving the sheet from the reference position to a stacking position.