A density correction unit (a1) obtains density measurement values of a surface in a measurement section of an image carrier at a first round, (a2) calculates as section background data at the first round respective differences between the density measurement values at the first round and an average value thereof, (a3) obtains density measurement values of a surface at least in the measurement section at a second round, (a4) calculates as section background data at the second round respective differences between the density measurement values at the second round and an average value thereof in a specific section with the same length as the measurement section, and (a5) determines the rotation period on the basis of a correlation between the section background data at the first round and at the second round. Here the measurement section is a part in a circulating direction of the image carrier.

An image forming apparatus capable of performing color misregistration correction at image forming speeds while reducing downtime. Image forming units form images of different colors. The formed images are transferred to an intermediate transfer belt. A pattern sensor detects color misregistration amounts of color patterns formed on the intermediate transfer belt. A CPU causes the image forming units to form first color patterns at a first speed and the pattern sensor to detect first color misregistration amounts, and causes the former to form second color patterns at a second speed different from the first speed and the latter to detect second color misregistration amounts. The CPU determines third color misregistration amounts at a third speed based on the first and second color misregistration amounts. The third speed is different from the first and second speeds.

An example image forming apparatus includes a printing portion to print an image on a print medium, a gate member at an outgoing side of the printing portion to selectively guide the print medium discharged from the printing portion to a first route or a second route, and a reading member in the first route to read the image from the print medium discharged from the printing portion.

An image forming apparatus includes an intermediate transfer member, a cleaning member, and an image forming unit having a developer carrier. During an image forming job, when a ratio of an amount of toner consumed to a distance that the developer carrier is rotationally driven is greater than a threshold value, the image forming unit forms a first toner supply image for supplying toner to the cleaning member in a predetermined period that is from a time at which a first toner image is transferred to the intermediate transfer member to a time at which a second toner image is transferred to the intermediate transfer member. When the ratio is less than the threshold value, the image forming unit forms a second toner supply image for supplying toner to the cleaning member in the predetermined period and having a density that is higher than a first toner supply image density.

An image forming device includes a transfer belt, a plurality of image forming units, a plurality of sensors, and a processor. The plurality of image forming units are arranged in a moving direction of the transfer belt, and form the toner images on the transfer belt. The plurality of sensors detect the toner images formed on the transfer belt. The processor determines a relative positional misalignment among the toner images formed by the plurality of image forming units based on detection results output from the plurality of sensors, and performs alignment control of adjusting formation timings of the toner images on the transfer belt in the plurality of image forming units based on a determination result. The processor further performs abnormality determination processing based on a difference value among the detection results output from the plurality of sensors, and outputs a determination result of the abnormality determination processing.

The present disclosure provides an image-forming apparatus, a correction control method and a storage medium. The apparatus includes an image carrier; a pattern-forming unit, configured to form a first detection pattern for density detection on the image carrier, where the first detection pattern includes a black first-sub-pattern and a non-black second-sub-pattern; and further configured to form a second detection pattern for misregistration detection on the image carrier, where the second detection pattern includes a full-color third-sub-pattern and a full-color fourth-sub-pattern, and the third-sub-pattern is different from the fourth-sub-pattern; a first sensor, configured to perform the density detection on the first-sub-pattern and the misregistration detection on the third-sub-pattern; and a second sensor, configured to perform the density detection on the second-sub-pattern, and the misregistration detection on the fourth-sub-pattern.

A control unit of an image forming apparatus can perform a density correction mode to correct toner density, based on detection results of toner density of a plurality of reference images formed with density gradations changed sequentially in a plurality of steps, detects presence or absence of a change in the voltage in each density gradation, based on the toner density detection value detected in the density correction mode, and if the density gradation has a specific density gradation in which a change in the voltage is detected, it corrects the toner density of the specific density gradation, using the detection values of density gradations before and after the specific density gradation.

An image forming apparatus that forms an image on a sheet based on an image forming mode, the image forming mode including a first image forming mode and a second image forming mode for forming an image which a maximum density different from a maximum density of an image in the first image forming mode, the image forming apparatus includes an image processor configured to convert an image signal based on a conversion condition, an image forming unit configured to form an image based on the image signal converted by the image processor, the image forming unit being controlled based on an image forming condition corresponding to the image forming mode, an image bearing member on which a pattern image is to be formed by the image forming unit, a sensor configured to detect the pattern image formed on the image bearing member.

In an image forming apparatus including a transfer member, a control unit, and a feeding unit including a blowing unit which blows air to leading edge portions of recording materials contained in a container, the control unit sets a transfer voltage for the transfer member during image formation based on detection results by a reading unit when a region to which at least one density acquisition image is to be transferred in a recording material on which a chart is formed is passing through a transfer portion, detection results when a predetermined region closer to the leading edge side than the region to which a plurality of density acquisition images is to be transferred in a conveyance direction of the recording material on which a chart is formed is passing through the transfer portion, and information about densities of the plurality of density acquisition images.

An image forming apparatus includes an apparatus body having a body frame, an image bearing member, a belt unit including a belt, and a stretching member configured to stretch the belt, the belt unit being pivotable around a first pivot axis between a first position and a second position, a transfer unit, and a detection unit movably supported by the body frame. The detection unit is configured to pivot around a second pivot axis different from the first pivot axis with respect to the body frame so as not to hinder pivoting of the belt unit in conjunction with a pivoting operation in which the belt unit pivots from the first position to the second position.