An image forming apparatus includes a fixing device having a heater that includes a first heating element, a second heating element having a length smaller than the first heating element length, and a third heating element having a length smaller than the second heating element length. The image forming apparatus further includes a first temperature detection unit, a control unit, second temperature detection units, first and second sheet-width detection units, and a determination unit. The control unit controls a heater temperature based on the first temperature detection unit detection result. The determination unit determines a width of the recording material based on a detection result of the first sheet-width detection units, a detection result of the second sheet-width detection units, and a detection result of the second temperature detection units.

Provided is an image forming apparatus including a printer controller configured to form an image on a sheet, a storage unit configured to store a plurality of adjustment conditions for adjusting a position on the sheet at which the image is to be formed, and a CPU. The CPU selects one of the plurality of adjustment conditions, adjusts the position at which the image is to be formed based on the selected adjustment condition, and causes the printer controller to form the image on the sheet.

A sheet conveying apparatus of an embodiment includes a conveyance path along which a sheet can be conveyed, and a plurality of conveyance rollers configured to move a sheet along the conveyance path. A wireless tag reader/writer is configured to read information from, and write information to, a wireless tag of a sheet on the conveyance path. A phase change detector is configured to detect a phase change in response waves received by the wireless tag reader/writer from a wireless tag. A tag specifying unit is configured to identify whether a wireless tag is moving along the conveyance path based on the detected phase change in response waves from the wireless tag. A controller controls the wireless tag reader/writer to write information to the wireless tag identified as moving along the conveyance path.

An image forming apparatus includes a controller configured to identify a selected sheet size setting as defined by a dimension in the width direction and a dimension in the conveyance direction, set a cooling threshold at a first threshold if the selected sheet size setting is a first size having a dimension in the width direction larger than a predetermined dimension, and a dimension in the conveyance direction larger than the dimension in the width direction, and set the cooling threshold at a second threshold lower than the first threshold if the selected sheet size setting is a second size having a dimension in the width direction that is the same as the dimension in the width direction of the first size, and a dimension in the conveyance direction smaller than the dimension in the width direction.

An image heating apparatus includes an image heating portion including a heater, a tubular film having an inner surface in contact with the heater, and a pressure member that is in contact with the outer surface of the film and forms a nip portion for conveying a recording material between the outer surface and the pressure member. The image heating portion heats an unfixed toner image on the recording material by the heater. A temperature detection portion detects the temperature of the heater. A control portion controls electric power to the heater such that the temperature detected by the temperature detection portion is maintained at a predetermined control target temperature. An obtainment portion obtains image information for forming the unfixed toner image. The control target temperature is set, based on the image information, for each of a plurality of regions defined by dividing the recording material in the conveying direction.

An image forming apparatus according to one or more embodiments includes a fixing device and a controller. The fixing device includes a first heating source and a second heating source. The second heating source has a heating width greater than that of the first heating source. The first and second heating sources have different heating characteristics in response to temperature increases. The controller selects one of the first heating source and the second heating source according to a size of a sheet on which printing is to be performed.

An image forming apparatus includes a sheet stacking portion, an image forming portion, a detection portion configured to detect a position, in a sheet width direction, a storage configured to store position information of a sheet, and a controller. The controller is configured to cause the storage to store the position information based on a position of a sheet detected by the detection portion during execution of the job, and if sheet information of a sheet used in a previous job is matches sheet information of a sheet used in a current job, cause the image forming portion to start formation of an image to be formed on a first sheet, before a position of the first sheet is detected by the detection portion, based on the position information stored in the storage in the previous job.

A conveyance device includes a first temperature detector and a second temperature detector that detect a temperature of a heater. A recording medium detector detects a recording medium. The first temperature detector is separated from a center position of an elastic layer of a pressure rotator farther than the second temperature detector is in an orthogonal direction perpendicular to a recording medium conveyance direction. The first temperature detector is separated from the center position for a first length and disposed in a first span defined by the center position in the orthogonal direction. The recording medium detector is disposed in a second span opposite to the first span, separated from the center position for a second length smaller than the first length, and disposed in a minimum recording medium conveyance span where the recording medium having a minimum width in the orthogonal direction is conveyed.

An image forming apparatus includes: a transporter; an image former; a reflective optical sensor; an image density adjuster; and a controller. The image former includes: a photoreceptor; a charger; an exposer; a developer; a transferor; and a fuser. The reflective optical sensor is provided opposite to the photoreceptor across a conveyance path. During image density adjustment, the controller forms a predetermined patch toner image on the photoreceptor, irradiates the patch toner image with light, and control the image density adjuster to adjust image density based on reflected light from the patch toner image. During image forming, the controller causes the reflective optical sensor to emit light on timing that a predetermined leading edge area of the recording area passes, and decides based on reflected light therefrom whether a width in the main scanning direction of a recording medium is longer than a predetermined reference length.

An image forming apparatus includes a fixing device having a heater, a first temperature detection unit, a pair of second temperature detection units, a pair of first sheet-width detection units, a pair of second sheet-width detection units, and a control unit. The heater includes a first heat generating element, a second heat generating element having a length smaller than a length of the first heat generating element in a longitudinal direction, and a third heat generating element having a length smaller than the length of the second heat generating element in the longitudinal direction. The control unit controls a temperature of the heater based on a detection result of the pair of first sheet-width detection units, a detection result of the pair of second sheet-width detection units, and a detection result of the pair of second temperature detection units.