In a sheet feeding apparatus, a recording material is stacked in a stacking unit, a sheet surface detection member takes on one of a first state, in which the sheet surface detection member displaces according to a height of a top surface of the material, and a second state. A detector detects the sheet surface detection member. A feeding unit is mounted in and removed from a main body. The feeding unit includes a feed roller and a switching unit that switches the sheet surface detection member to one of the first state and the second state. The switching unit switches the sheet surface detection member to the second state in response to the feeding unit being replaced, and a controller detects that the feeding unit has been replaced based on a state change detected by the detector.

An image forming apparatus includes a print portion that prints an image on a sheet passing by a print position, and an inserter that inserts an insert sheet between sheets conveyed one after another. In a print job involving an insert process, the print portion conveys, while securing an insert interval between a preceding sheet, which is a sheet immediately preceding the insert sheet, and a succeeding sheet, which is a sheet immediately following the insert sheet, the preceding sheet and the succeeding sheet one after another. The print portion automatically changes the insert interval according to the length of the insert sheet in the conveyance direction.

An image forming apparatus includes a print portion that prints an image on a sheet passing by a print position, and an inserter that inserts an insert sheet between sheets conveyed one after another. In a print job involving an insert process, the print portion conveys, while securing an insert interval between a preceding sheet, which is a sheet immediately preceding the insert sheet, and a succeeding sheet, which is a sheet immediately following the insert sheet, the preceding sheet and the succeeding sheet one after another. The print portion automatically changes the insert interval according to the length of the insert sheet in the conveyance direction.

A sheet processing apparatus including a stapler for executing a stapling process, a sheet detection sensor for detecting a sheet as a processing target, and an execution button for receiving from a user an execution instruction to execute the stapling process, after the sheet detection sensor detects a sheet, in a case where the execution button is pressed before a predetermined time elapses, causes the stapler to execute the stapling process according to the execution button being pressed, and in a case where the execution button is not pressed, causes the stapler to execute the stapling process according to lapse of the predetermined time. Further, the sheet processing apparatus sets whether the execution of the stapling process according to the lapse of the predetermined time is enabled.

A sheet processing apparatus including a stapler for executing a stapling process, a sheet detection sensor for detecting a sheet as a processing target, and an execution button for receiving from a user an execution instruction to execute the stapling process, after the sheet detection sensor detects a sheet, in a case where the execution button is pressed before a predetermined time elapses, causes the stapler to execute the stapling process according to the execution button being pressed, and in a case where the execution button is not pressed, causes the stapler to execute the stapling process according to lapse of the predetermined time. Further, the sheet processing apparatus sets whether the execution of the stapling process according to the lapse of the predetermined time is enabled.

A method for rapidly stacking and dropping sheets is provided. The method comprises receiving a plurality of sheets from a sheet delivery device onto a landing platform of a stacking and dropping apparatus. The method also comprises lowering the landing platform from an original upper position. Lowering comprises maintaining a drop height between the sheet delivery device and a stack of delivered sheets. The method also comprises sending a delay signal that comprises a command to delay the receiving of the plurality of sheets from the sheet delivery device. The delay signal is sent in response to a detection of a predetermined stack height of the stack of delivered sheets. The method also comprises sending a movement signal, immediately following the sending of the delay signal. The movement signal comprises a command to move the landing platform, such that the plurality of sheets are received by a catch tray unit. The method also comprises dropping, utilizing the catch tray unit, the plurality of sheets onto a sheet receiving device. The method also comprises returning, automatically, the landing platform to the original upper position. The method also comprises sending a resume signal, that includes a command to the sheet delivery device to resume sheet delivery. The delay signal, movement signal and resume signal are sent by a central processor component of the stacking and dropping apparatus.

A method for rapidly stacking and dropping sheets is provided. The method comprises receiving a plurality of sheets from a sheet delivery device onto a landing platform of a stacking and dropping apparatus. The method also comprises lowering the landing platform from an original upper position. Lowering comprises maintaining a drop height between the sheet delivery device and a stack of delivered sheets. The method also comprises sending a delay signal that comprises a command to delay the receiving of the plurality of sheets from the sheet delivery device. The delay signal is sent in response to a detection of a predetermined stack height of the stack of delivered sheets. The method also comprises sending a movement signal, immediately following the sending of the delay signal. The movement signal comprises a command to move the landing platform, such that the plurality of sheets are received by a catch tray unit. The method also comprises dropping, utilizing the catch tray unit, the plurality of sheets onto a sheet receiving device. The method also comprises returning, automatically, the landing platform to the original upper position. The method also comprises sending a resume signal, that includes a command to the sheet delivery device to resume sheet delivery. The delay signal, movement signal and resume signal are sent by a central processor component of the stacking and dropping apparatus.

A post-processing apparatus of an embodiment includes a first tray configured to receive a sheet on which the post processing is not executed by a processing section, a second tray configured to temporarily place a sheet, an inlet roller configured to carry in a sheet discharged from an image forming apparatus into the post-processing apparatus, a first roller configured to convey the sheet to the first tray, a second roller configured to convey the sheet to the second tray, a detection sensor configured to detect whether or not there is sheet being conveyed in a sheet conveyance path from the inlet roller to the first or the second tray, and a roller control section configured to drive the first or the second roller if an image forming apparatus stops the discharge of the sheet that is being printed and the detection sensor detects the sheet.

Detecting a continuous level of paper in a paper supply providing paper for a printing device. A length of the paper supply includes applied indicia, with the indicia extend contiguously across the length of the paper supply. When a paper section is dispensed, the position of the indicia on the dispensed portion of paper is determined, with the position reflecting a level pertaining to the paper supply remaining or dispensed.

Detecting a continuous level of paper in a paper supply providing paper for a printing device. A length of the paper supply includes applied indicia, with the indicia extend contiguously across the length of the paper supply. When a paper section is dispensed, the position of the indicia on the dispensed portion of paper is determined, with the position reflecting a level pertaining to the paper supply remaining or dispensed.