A paper feed device includes: a sensor unit that includes a coil substrate and a conductive plate which is opposite the coil substrate, that outputs an output value corresponding to a position of the conductive plate; a first cursor link mechanism which moves the first conductive plate according to the position of the first cursor in the longitudinal direction of the first coil substrate; a storage unit which stores first sheet size data; and a control unit which recognizes the magnitude of the first output value of the sensor unit and which recognizes, based on the recognized magnitude of the first output value and the first sheet size data, the size of the set sheets.

A paper feed device includes: a sensor unit that includes a coil substrate and a conductive plate which is opposite the coil substrate, that outputs an output value corresponding to a position of the conductive plate; a first cursor link mechanism which moves the first conductive plate according to the position of the first cursor in the longitudinal direction of the first coil substrate; a storage unit which stores first sheet size data; and a control unit which recognizes the magnitude of the first output value of the sensor unit and which recognizes, based on the recognized magnitude of the first output value and the first sheet size data, the size of the set sheets.

An image forming apparatus is provided that forms an image on a sheet material based on a sheet material setting relating to the sheet material. The image forming apparatus includes an accepting unit configured to accept a selection of a sheet material type, a thickness measurement unit configured to measure a thickness of the sheet material, and a setting determination unit configured to determine the sheet material setting that relates to the thickness of the sheet material based on the sheet material type accepted by the accepting unit and the thickness of the sheet material measured by the thickness measurement unit.

This paper sheet processing device (100) for processing paper sheets is provided with: an identification unit (55) for identifying paper sheets; stacking units (60, 210) for stacking paper sheets on the basis of the content of classification types identified by the identification unit (55); and a control unit (50, 135, 550) that reads, from a memory unit (56, 136, 560) in which an upper limit of paper sheets to be stacked by the stacking units (60, 210) are stored in association with the content of classification types, the upper limit for paper sheets that correspond to the content of the classification types of the paper sheets stacked by the stacking units (60, 210), and sets the upper limit for paper sheets to be stacked by the stacking units (60, 210).

This paper sheet processing device (100) for processing paper sheets is provided with: an identification unit (55) for identifying paper sheets; stacking units (60, 210) for stacking paper sheets on the basis of the content of classification types identified by the identification unit (55); and a control unit (50, 135, 550) that reads, from a memory unit (56, 136, 560) in which an upper limit of paper sheets to be stacked by the stacking units (60, 210) are stored in association with the content of classification types, the upper limit for paper sheets that correspond to the content of the classification types of the paper sheets stacked by the stacking units (60, 210), and sets the upper limit for paper sheets to be stacked by the stacking units (60, 210).

A sheet loading device is provided with a sheet ejection portion, a sheet loading portion, a first detection mechanism, a driving device, a second detection mechanism, and a control portion. The driving device drives the sheet loading portion to ascend/descend between an upper surface detection position and a reference position made to descend by a prescribed distance from the upper surface detection position. The second detection mechanism detects that the sheet loading portion is at the reference position. In a case where sheets of the same type are ejected continuously from the sheet ejection portion, the control portion controls beforehand the sheet loading portion to ascend from the reference position to the upper surface detection position and sets a loadable number of sheets of the sheet loading portion in accordance with an ascending time of the sheet loading portion.

A sheet loading device is provided with a sheet ejection portion, a sheet loading portion, a first detection mechanism, a driving device, a second detection mechanism, and a control portion. The driving device drives the sheet loading portion to ascend/descend between an upper surface detection position and a reference position made to descend by a prescribed distance from the upper surface detection position. The second detection mechanism detects that the sheet loading portion is at the reference position. In a case where sheets of the same type are ejected continuously from the sheet ejection portion, the control portion controls beforehand the sheet loading portion to ascend from the reference position to the upper surface detection position and sets a loadable number of sheets of the sheet loading portion in accordance with an ascending time of the sheet loading portion.

A sheet feeder includes a manual feeding tray to stack a sheet, the tray being openable and closable to a main body by rotation about a rotation axis in a direction perpendicular to a sheet feeding direction; a sheet width regulating member provided in the manual feeding tray to regulate a side edge of the sheet in a sheet width direction and to have a variable regulating width; an auxiliary tray that does not move with an opening/closing operation of the manual feeding tray and stacks the sheet with the manual feeding tray; a sheet width regulating member provided in the auxiliary tray to regulate the side edge of the sheet and to have a variable regulating width; a link member interlocking the regulating members; and a feeding roller provided in the main body to individually feed the sheet stacked over the manual feeding tray and the auxiliary tray.

A sheet feeder includes a manual feeding tray to stack a sheet, the tray being openable and closable to a main body by rotation about a rotation axis in a direction perpendicular to a sheet feeding direction; a sheet width regulating member provided in the manual feeding tray to regulate a side edge of the sheet in a sheet width direction and to have a variable regulating width; an auxiliary tray that does not move with an opening/closing operation of the manual feeding tray and stacks the sheet with the manual feeding tray; a sheet width regulating member provided in the auxiliary tray to regulate the side edge of the sheet and to have a variable regulating width; a link member interlocking the regulating members; and a feeding roller provided in the main body to individually feed the sheet stacked over the manual feeding tray and the auxiliary tray.

An image forming apparatus includes a sheet cassette, a sheet conveying portion, an image forming portion, a position detecting portion, and an image position correcting portion. The sheet conveying portion conveys a sheet from the sheet cassette attached to the apparatus main body, along a sheet conveyance path whose width direction matches the main direction. The position detecting portion detects a position of a detection-target portion that is a part of the sheet cassette, in the main direction based on the apparatus main body. The image position correcting portion corrects an image formation position in the main direction at which the image is formed by the image forming portion, based on the position detected by the position detecting portion.