An image forming apparatus includes a control unit configured to execute a first mode and a second mode. The first mode is a mode in which a toner image is formed on a sheet at a time when a sheet passes through an image formation position for a first time after detecting a property of the sheet by a detection unit. Wherein the second mode is a mode in which a toner image is not formed on a sheet at the time when the sheet passes through the image formation position for the first time after detecting the property of the sheet by the detection unit and is formed on the sheet at a time when the sheet is conveyed via the second conveyance path and passes through the image formation position for a second time.

An image forming apparatus comprising includes an image carrying member including a movable surface to include a toner image; a transfer roller to form a transfer nip between the transfer roller and the movable surface of the image carrying member, to move position in a direction in correspondence to a thickness of a print medium to intersect a direction of introduction of the print medium into the transfer nip, and to receive a transfer bias voltage to transfer the toner image from the movable surface of the image carrying member to the print medium; and a movement guide structure to guide the print medium toward the transfer nip, and to move in synchronization with the movement of the position of the transfer roller to change a gap between an end of the movement guide structure facing the image carrying member and the image carrying member.

An image formation apparatus includes: a transferrer that forms a toner image on an image formation surface of paper; a fixer that fixes the toner image on the paper; a paper conveyor that conveys the paper between an upstream side of the transferrer and a downstream side of the fixer in a paper conveyance direction; and a paper pre-heater that heats, on the upstream side of the transferrer in the paper conveyance direction, the image formation surface of the paper.

An automatic detection method for a paper size is disclosed. a plurality of mark points is set on a paperweight along a paperweight direction that is different from a feeding direction. The disclosure senses a plurality of row images combining into a scan image during a paper passing between the paperweight and an image sensor, determines an edge length of the paper based on a range of the mark points covered by the paper, and determines a paper size based on the edge length. The disclosure can effectively detect the paper size without any additional sensors.

A static elimination device includes: a first static elimination member that makes contact with a medium that is transported; a second static elimination member arranged such that the medium is inserted between the first static elimination member and the second static elimination member; and a power source that applies a voltage to at least one of the first static elimination member or the second static elimination member, in which at least one of the first static elimination member and the second static elimination member has an elastic body.

A control device of an image forming system including an image former that forms an image on a recording medium formed of a continuous sheet or a long sheet includes a hardware processor that calculates a width of the recording medium on a downstream side of a fixer included in the image former in a transport direction of the recording medium and outputs a shrinkage amount or a shrinkage rate of the recording medium in the transport direction due to the fixer based on the width of the recording medium and shrinkage characteristic information of the recording medium.

A sheet processing system for automated sheet adjustment includes a sensor system which captures at least a first image of a sheet of print media as the sheet is conveyed on a main transport path between a print media supply module and a marking device of an image rendering module. A control module computes a lateral error for the sheet, based on the captured at least first image, and computes an adjustment based on the computed lateral error. A sheet transport path adjustment mechanism translates a first portion of the main transport path relative to a second portion of the main transport path, based on the computed adjustment.

A calculation system includes an obtaining unit and a calculation unit. The obtaining unit obtains information of a sheet. The calculation unit calculates an amount of change in length of the sheet in a conveyance direction of the sheet heated by a heating device to fix a toner image to the sheet based on the information of the sheet obtained by the obtaining unit and an elapsed time from a time when the sheet passes through the heating device.

An image formation apparatus includes: an image former that prints an image on paper; a corrector that corrects a print position of the image on the paper; and a first sensor that is disposed on a conveyance path upstream of the image former, detects paper, and outputs detection data to the corrector, wherein the corrector obtains, on the basis of the detection data, an amount of change in a shape of first paper from a shape of second paper printed before the first paper is printed, and corrects a print position of a first image on the first paper on the basis of the change amount.

An image forming apparatus includes an image bearing member, an image forming portion, a transfer member, an applying portion, and an executing portion configured to execute an output operation for forming and outputting a chart formed on a recording material on which a plurality of test images are transferred by applying a plurality of voltages to the transfer member by the applying portion. The executing portion changes a change width per level of the test voltage so that the change width is a first change width in a case that a material of the recording material on which the chart is formed is a first material and so that the change width is a second change width different from the first change width in a case that the material of the recording material is a second material different from the first material.