A fixing device includes a fixing rotator over which a recording medium bearing an image is conveyed. A first heater heats the fixing rotator and generates heat evenly in a maximum conveyance span where the recording medium having a maximum width in a width direction of the recording medium is conveyed. The maximum width is available for the fixing rotator. A second heater heats the fixing rotator and generates heat in the maximum conveyance span. The second heater includes a first portion that generates heat in a first heat generation amount and a second portion that generates heat in a second heat generation amount that is greater than the first heat generation amount of the first portion.

An image forming apparatus includes: an image bearing member that carries a developer image; a transfer member that forms a transfer nip portion with the image bearing member and transfers the developer image in the transfer nip portion from the image bearing member to a recording material; a fixing portion that includes a heater and fixes the developer image to the recording material using heat of the heater; a temperature detection portion that detects a temperature of the fixing portion; a control portion that controls power supplied to the heater such that the temperature detected by the temperature detection portion becomes a predetermined control target temperature; and an acquisition portion that acquires a temperature of the image bearing member or the transfer member. The control target temperature is changed based on the temperature acquired by the acquisition portion.

In an image forming apparatus, a cleaning blade, disposed on a downstream side of a transfer roller in a rotation direction of an image carrier, removes toner remaining on the image carrier after transfer of a toner image to an intermediate transfer member. After completion of an image forming operation, a controller causes the transfer roller to separate from the intermediate transfer member, cause the developing device to form on the image carrier a toner band to be supplied to the cleaning blade, and cause rotation of the image carrier to stop such that at least a part of the toner band formed on the image carrier stops within a section from a first position facing the transfer roller to a second position facing the cleaning blade in the rotation direction.

In an image forming system including an apparatus main-body and a control portion which controls a fixing operation, to the apparatus main-body, a first fixing unit including a first heater and a second fixing unit including a second heater, which is different from the first heater, can be selectively attached, and each of the first and second fixing units has an information processing portion which transmits data including identification information and temperature information related to a temperature detected by a temperature detection element to the control portion, and the control portion discriminates which of the first fixing unit and the second fixing unit, the fixing unit attached to the apparatus main-body is on the basis of the identification information from the information processing portion and controls the fixing operation by the fixing unit on the basis of the temperature information.

An image forming apparatus includes an image forming unit, a fixing unit, a plurality of exterior covers forming an exterior of the image forming apparatus, a fan configured to suck outside air into the image forming apparatus through an air intake port, a temperature sensor configured to detect a temperature of the outside air sucked by the fan, and a partition member disposed upstream the temperature sensor and downstream the air intake port in an airflow generated by the fan, the partition member dividing an air intake path through which the outside air sucked through the air intake port passes into a first path passing through a fixing unit side and a second path passing through a temperature sensor side.

A fixing apparatus includes a heater including a heating member, a heater holder configured to hold the heater, a detection element configured to detect a temperature of the heater and disposed at a position that faces the heater in a third direction, a first holding member configured to hold the detection element, an urging member configured to urge the first holding member, a flexible member extending in the first direction and configured to support the first holding member on a first end portion of the flexible member in the first direction, and a second holding member configured to hold a second end portion of the flexible member in the first direction. The flexible member is flexible such that the first holding member and the second holding member are movable relative to each other in the third direction.

An image forming apparatus includes a main body housing, a first cartridge to store first developer, a second cartridge to store second developer, a first temperature sensor to detect an inside temperature as a temperature inside the main body housing, and a controller configured to calculate a first control temperature corresponding to the first cartridge, using the detected inside temperature and a first coefficient to be multiplied by the inside temperature, calculate a second control temperature corresponding to the second cartridge, using the detected inside temperature and a second coefficient to be multiplied by the inside temperature, the second coefficient being different from the first coefficient, and perform cooling control to cool an inside of the main body housing when at least one selected from the first control temperature and the second control temperature is higher than a particular threshold.

An image forming apparatus controls the number of rotations of a photosensitive drum based on information related to the use of the photosensitive drum and a suspension time in a rotation operation of rotating the photosensitive drum after a lapse of the suspension time between a first image forming operation of forming an image on a transfer material and a second image forming operation performed after the first image forming operation.

An image forming apparatus with accurate color shift correction with consideration of a change in a rotational speed of a driving portion of a laser scanning member includes a light source, the laser scanning member, a driving portion, a speed controlling portion, a light detecting portion, a light source controlling portion, a scanning lens, a housing, a temperature gradient detecting portion, a first temperature detecting portion, and a correction processing portion. The temperature gradient detecting portion detects a temperature gradient in the housing. The first temperature detecting portion detects a temperature of the scanning lens. The correction processing portion corrects an emission start timing at which light corresponding to a line of image data is emitted from the light source, based on the temperatures detected by the temperature gradient detecting portion and the first temperature detecting portion, the rotational speed of the driving portion, and a preset arithmetic expression.

An image forming apparatus includes a fixing unit including a heater; a bidirectional thyristor for supplying electric power form an AC power source to the heater in a conduction state and for cutting off supply of the electric power from the AC power source to the heater in a non-conduction state; a control unit for outputting a control signal for controlling the conductive state or the non-conduction state of the bidirectional thyristor; and a DC voltage source for supplying electric power for conduction of the bidirectional thyristor by the control signal outputted from the control unit. The control unit controls the heater in a predetermined control cycle on a one half-wave unit basis of an AC voltage of the AC power source. The control unit outputs a plurality of control signals in one half-wave of the AC voltage.