According to an embodiment, a heating device includes a cylindrical belt, a heater, a press roller, and a holder. The heater is disposed on an inner surface of the belt. The press roller rotates and is configured to contact an outer surface of the belt at a position opposite the heater to form a nip. The end portions of the press roller project by a first amount in a radial direction more than the central portion of the press roller. A holder has a first surface supporting the heater to face the cylindrical belt. The holder has a second surface that is opposite of the first surface with a center portion projecting in a direction orthogonal to the first surface more than the end portions of the second surface by a second projection amount that is greater than the first projection amount.

A fixing apparatus includes a first rotary member, a heating element, a second rotary member, a nip member, a reflection member, and a support member. The support member configured to transit to a pressurized state and a non-pressurized state, the pressurized state being a state in which a first position and a second position of the support member are pressurized in a pressurization direction toward the second rotary member, the non-pressurized state being in which the pressurized state of the support member is released. The support member includes a contact surface in contact with the reflection member in the pressurized state. The contact surface takes such a posture that a center position between the first and second positions in the rotation axial direction is close to the second rotary member rather than the first and second positions in a case where the support member is in the non-pressurized state.

There is provided an image forming apparatus and method, in which performed are reading an image of an original document, converting a read image to raster data, raising a temperature of a fixing device to a fixing temperature, after raising the temperature of the fixing device, recording an image on the sheet on a sheet and causing the fixing device to fix the developing agent image onto the sheet. When a preview setting is enabled, after performing the converting, the preview image is displayed on the display and the raising is performed after the displaying and in response to an execution instruction of the forming. When the preview setting is not enabled, after performing a pre-heating of the fixing device so that the temperature of the fixing device is lower than the fixing temperature, performing the raising without displaying the preview image.

According to an embodiment, a heater includes a heat-resistant insulating substrate, a plurality of heat generating members arrayed on a first surface of the insulating substrate, and a heat radiating body disposed on a surface different from the first surface of the insulating substrate corresponding to gap portions among the plurality of heat generating members and configured to actively or passively radiate stored heat.

In general, a fixing device according to an embodiment includes an endless belt, a pressure element, a heating member, an adjustment mechanism, and a controller. The pressure element conveys a sheet while interposing the sheet under pressure between the same and the endless belt. The heating member is provided on the inner side of the endless belt and has a heat generating element for heating the endless belt. The adjustment mechanism moves at least one of the heating member and the pressure element in such a direction as to bring the one closer to or away from the other, to adjust the nip width which is the length of an interposing and pressurizing region in a sheet conveyance direction, the interposing and pressurizing region being formed by the heating member and the pressure element to interpose the endless belt under pressure. The controller controls the adjustment mechanism so that A>B≧N is satisfied, where A is the nip width during a fixing process in which the sheet is heated to fix a color material onto the sheet, B is the nip width during temperature raising of the heating member to be conducted before the fixing process, and N is the length of the heat generating element in the sheet conveyance direction.

A fixing device includes a rotatable endless belt; a planar heat-generating section in which at least a downstream end portion in a movement direction of the belt is in pressure contact with a rotating body via a pressure contact portion and a cross-sectional shape of a downstream edge portion being in contact with an inner surface of the belt is formed in a curved shape having a curvature radius of 0.01 mm or more 0.2 mm or less or in a shape in which the edge portion is cut out over the dimension; and a holding section that is disposed inside the belt and holds the planar heat-generating section to be in pressure contact with the rotating body.

A fixing device includes: a fixing belt with no ends configured to stretch rotatably; a heating unit configured to heat the fixing belt; a fixing member disposed outside the fixing belt and configured to be in contact with the fixing belt by pressurizing; a pressing member disposed inside the fixing belt and configured to press the fixing member with the fixing belt involved; and a lubricant supply unit configured to supply a lubricant to the inner periphery of the fixing belt so as to supply the lubricant between the pressing member and the fixing belt, wherein the lubricant supply unit is disposed inside the fixing belt, configured to hold the lubricant, and includes a holding unit provided with a lubricant ejection port having a longitudinal shape and extending along a width direction of the fixing belt.

A fixing device includes a belt having a tubular shape and extending in a longitudinal direction, and having a longitudinal end, a drive roller to rotate the belt to convey a print medium between the drive roller and the belt, a bushing located at the longitudinal end of the belt, and a guide wall adjacent to the bushing. The belt is displaceable in the longitudinal direction relative to the bushing. The bushing includes a shoulder adjacent to the longitudinal end of the belt and a stem extending from the shoulder to an inside of the belt to support the belt. The guide guides the bushing to move in a direction opposite to a conveyance direction of the print medium when the belt moves toward the bushing. The stem of the bushing includes a convex portion that is in contact with an inner surface of the belt when the belt is displaced in the longitudinal direction.

Method of heating control includes preheating a heater to a first target temperature when an image forming device is powered on, is woken up from sleep, or receives a task to be processed; determining a voltage parameter of the heater or a characteristic of temperature change of a heating process of the heater, under the current environment of the power supply, according to a prior-preheating temperature, a post-preheating temperature, and a time length of the preheating; and according to the voltage parameter or the characteristic of temperature change under the current environment of the power supply, determining a heating start time of a second heating for the preheated heater and triggering the second heating at the heating start time, to allow a temperature of the heater to reach a second target temperature within a set time before an image to-be fixed arrives at the fixing assembly.

A nip forming device includes an endless belt that is flexible and rotates and a nip former that is disposed opposite an inner circumferential face of the endless belt. A pressure rotator presses against the nip former via the endless belt to form a nip between the endless belt and the pressure rotator, through which a conveyed object is conveyed. A separator is disposed downstream from the nip in a conveyance direction of the conveyed object. The separator separates the conveyed object from the endless belt. The separator includes a non-contact portion separated from the endless belt and a contact portion that contacts the endless belt. The contact portion retains a gap having a predetermined size between the non-contact portion and the endless belt.