Provided are a sheet position detection apparatus, a sheet conveyance apparatus, and an image formation apparatus. The sheet position detection apparatus has a first and a second conveyance roller which are arranged to oppose across a sheet to be conveyed and to nip the sheet, and a detector configured to detect an end position of the sheet, the detector has a light emitter and a light receptor arranged on the first conveyance roller side, the light emitter and the light receptor are arranged such that a light emitted from the light emitter is reflected on a reflective face of the second conveyance roller and enters the light receptor, and the detector detects passage of an end of the sheet based on a change in the amount of light entering the light receptor when the sheet shields a light emitted from the light emitter.

This disclosure relates to a banknote validator. The banknote validator comprises a banknote path formed within an interior of the banknote validator to transport a banknote from an opening of the banknote path through an interior of the banknote validator, a banknote imaging zone defined within a portion of the banknote path, the banknote imaging zone including a reflective region in a first portion of the banknote imaging zone, and a dark region in a second portion of the banknote imaging zone, and an image sensor configured to capture one or more images of at least a portion of the banknote imaging zone.

A sheet processing apparatus includes an entry portion, a sheet conveyance path extending from the entry portion, a skew correction roller pair that contacts a leading edge of a sheet conveyed in a predetermined direction from the entry portion to correct skew of the sheet, and a receiving path. The skew correction roller pair conveys the skew-corrected sheet in a direction opposite the predetermined direction. The receiving path branches from the sheet conveyance path from the entry portion to the skew correction roller pair to receive the sheet conveyed in the direction opposite the predetermined direction.

Alignment apparatuses include a frame and contact elements connected to the frame. The contact elements contact items that are to be transported in a processing direction relative to the frame. The contact elements are in permeant fixed positions relative to the frame, and do not move relative to the frame. Adjustable mounts are connected to the frame and move the frame in the processing direction and in a perpendicular cross-processing direction. A controller is electrically connected to the adjustable mounts, and the controller is adapted to control the adjustable mounts to simultaneously move the frame and all the contact elements in the cross-processing direction and the processing direction while rotating the frame. Methods laterally shift imaging on sheets that have had rotational correction performed by such alignment apparatuses.

A printing apparatus comprises a conveyance control unit which controls conveyance of printing sheets so that a trailing edge of a preceding sheet as a printing sheet precedingly fed from the stacking unit and a leading edge of a succeeding sheet as a printing sheet succeedingly fed from the stacking unit overlap each other; and a skew correction unit which performs skew correction of the succeeding sheet while the succeeding sheet overlaps the preceding sheet by the conveyance control unit. The skew correction unit makes the leading edge of the succeeding sheet abut against the conveyance roller during a time from an end of a last line feed operation by the conveyance roller for printing on the preceding sheet by the printing unit to start of a next conveyance operation.

A sheet conveyance apparatus includes a first roller pair, a second roller pair, an abutment portion, an oblique feeding portion, a detection portion, a moving portion a contact/separation portion, and a control portion. If a first sheet whose length is a first length is conveyed, the control portion causes the moving portion to move the first roller pair, and then causes the first sheet to be conveyed from the first roller pair to the oblique feeding portion through the second roller pair that is in the separation state, and if a second sheet whose length is a second length shorter than the first length is conveyed, the control portion causes the moving portion to move the first roller pair, and then causes the second sheet to be conveyed from the first roller pair to the oblique feeding portion via the second roller pair that is in the contact state.

A sheet conveyance device includes a conveyance roller pair. A skew correction roller pair conveys the sheet after contacting two nip portions, and a sheet skew is corrected in a state in which the skew correction roller pair is being stopped. The sheet having a toner image is bent by a first conveyance guide such that a sheet first surface becomes an inside surface. The sheet is bent by the first and second conveyance guides to cause the sheet first surface to be the inside surface and a sheet second surface to be an outside surface. The skew correction roller pair includes two first rotary members of a first roller. A second roller and the two first rotary members form the two nip portions. The second roller and the first conveyance guide contact the sheet first surface. The first roller and the second conveyance guide contact the sheet second surface.

A center-alignment apparatus for use in an ATM has a transport mechanism to transport a document into the ATM. One or more plates operable in tandem to move the document toward a centerline of a path the document is to travel. Edge-detection sensor(s) on the plate sense an edge of the document when the plate(s) is moved toward the centerline. A translate/rotate mechanism translates and rotates the document while the translate/rotate mechanism transversely moves the document toward the center until another edge-detection sensor detects an edge of the document to create a parallel-aligned document. The control logic controls the plate(s) to centers the parallel-aligned document about the centerline to create a centered document.

A sheet conveying device includes a detector configured to detect an attitude of a conveyance target medium, a corrector configured to perform a correcting operation based on a detection result of the detector, and circuitry configured to calculate an angular displacement correction amount and a lateral displacement correction amount of the conveyance target medium, cause the corrector to perform the correcting operation in a direction perpendicular to a sheet conveying direction, based on the lateral displacement correction amount, after the corrector grips the conveyance target medium, and cause the corrector to rotate by the angular displacement correction amount of the conveyance target medium before the corrector grips the conveyance target medium and to perform the correcting operation in a direction of rotation of the conveyance target medium, based on the angular displacement correction amount, after the corrector grips the conveyance target medium.

A sheet conveying device, which is included in an image forming apparatus and a post processing device, includes multiple position detectors and a position corrector. The multiple position detectors are aligned along a sheet conveying direction and configured to detect a side end of a sheet. The position corrector is configured to convey the sheet and correct a position of the sheet based on a positional deviation amount of the sheet, obtained by a detection result of the multiple position detectors. The positional deviation amount of the sheet is obtained by an extreme downstream position detector in the sheet conveying direction, of the multiple position detectors. A position of a subsequent sheet is corrected based on a sum of the positional deviation amount of the sheet and a positional deviation amount of the subsequent sheet.