An image forming apparatus includes a housing having an opening, a cover configured to open the opening in an open state and to close the opening in a close state, a photosensitive drum, a heater, a fan configured to force air out of the housing, and a controller. The cover in the open state is configured to allow a sheet with a toner image fixed thereon to be ejected through the opening. The heater is configured to heat a sheet to fix a toner image on the sheet, and is located between the cover in the close state and the photosensitive drum. During execution of a printing process, the controller is configured to cause the fan to rotate at a first speed if the cover is in the closed state, and to rotate at a second speed lower than the first speed if the cover is in the open state.

According to one embodiment, a fixing device, includes a fixing member having a first surface configured to be pressed against a recording medium and a heater on a second surface of the fixing member. A first heat conducting member contacts aback surface side of the heater, and a second heat conducting member is provided to be moveable between a first state, in which the second heat conducting member is in contact with the first heat conducting member and the second surface of the fixing member, and a second state, in which the second heat conducting member is contacting the first heat conducting member, but separated from the second surface of the fixing member.

A fixing device includes a movable belt; and a planar heat-generating section that is in contact with the belt and in which, among plural heat-generating portions provided in a movement direction of the belt, a heat-generating portion on an upstream side in the movement direction of the belt has a larger heat generation amount than a heat-generating portion on a downstream side.

In an image heating apparatus, a plurality of heat-generating members that a heater has include a first heat-generating member group and a second heat-generating member group, symmetrically laid out with a conveyance reference position of a recording material. A control portion supplies electric power via first and second common circuits to the first heat-generating member group and the second heat-generating member group. A temperature-detecting portion includes a first temperature-detecting element for detecting a temperature of one of the heat-generating members included in the first heat-generating member group, and a second temperature-detecting element for detecting the temperature of one of the heat-generating members included in the second heat-generating member group. The first temperature-detecting element is placed on one side as to the conveyance reference position in the width direction, and the second temperature-detecting element is placed on other side as to the conveyance reference position in the width direction.

An image forming apparatus includes a temperature sensor, a conveyance control portion, a driving control portion, an adjustment processing portion, and a stop processing portion. The temperature sensor is provided apart from a contact position between a fixing member and a transferred sheet to which a toner image has been transferred. The conveyance control portion continuously executes conveyance processes of conveying the transferred sheet. The driving control portion controls driving of a heater for heating the fixing member so that a temperature detected by the temperature sensor matches a predetermined temperature. The adjustment processing portion restricts the execution of the conveyance process until an adjustment process of adjusting a formation condition of the transferred sheet is completed. The stop processing portion stops the continuous execution of the conveyance processes when the restriction on the execution of the conveyance process continues beyond a predetermined timing.

A heater includes a heat generating member in a first layer, a sensor that is in a second layer different from the first layer and configured to detect a temperature of the heat generating member, and a wiring pattern in one or more third layers between the first and second layers to supply power to the heat generating member.

An image forming apparatus is operable in a first small-sheet printing in which power is supplied to the first heat generating element and the second heat generating element and in a second small-sheet printing in which power is supplied to the first heat generating element and the third heat generating element. A first power ratio, which is a proportion of power supplied to the first heat generating element to power supplied to the second heat generating element in the first small-sheet printing, is higher than a second power ratio, which is a proportion of power supplied to the first heat generating element to power supplied to the third heat generating element in the second small-sheet printing.

In an image forming device, a first fixing member has a roller. A second fixing member has a belt to form a nip together with the first fixing member. A first motor drives the roller. A pressure modifying mechanism modifies a nip pressure at the nip to selected one of a first nip pressure and a second nip pressure smaller than the first nip pressure. A controller starts driving the first motor to drive the roller in a case where a print command is received in a state that the nip pressure is the second nip pressure. The controller modifies the nip pressure from the second nip pressure to the first nip pressure after the driving is performed and fixes the developer image on the sheet in a state that the nip pressure is the first nip pressure.

According to an embodiment, an image forming apparatus measures a temperature of a pressing member and controls heat generation of a heater such that the measured temperature approaches a control temperature. Further, the image forming apparatus sets, before starting image formation of one job including image formation, one candidate temperature of a plurality of predetermined candidate temperatures different from each other as the control temperature on the basis of the number of sheets to be used and a sheet size to be used in the image formation of the one job.

An image forming apparatus includes an image forming unit configured to form a toner image on a recording material, a fixing unit configured to fix the toner image formed on the recording material by the image forming unit to the recording material, and a controller configured to cause the image forming unit to form an image on a basis of image information, the controller being configured to cause the image forming unit to form the image in which a first toner image and a second toner image is superimposed on each other on the recording material, the first toner image being a toner image corresponding to the image information, the second toner image being constituted by a pattern having anisotropy such that glossiness of the image changes depending on a direction in which the image is viewed.