A fixing device includes a first roller that is arranged in a region where an image formed on a recording medium is fixed to the recording medium and that heats the recording medium, a second roller that is arranged to face the first roller in the region and pressurizes the recording medium toward the first roller, a fan that sends air to the second roller, and a processor configured to control the fan, in which the second roller has a shape in which a diameter of an end portion in a longitudinal axis direction is larger than a diameter of a central portion in the longitudinal axis direction, the first roller and the second roller fix the image to the recording medium in the region, and the processor is configured to change a rotation speed of the fan between the central portion and the end portion of the second roller.

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 heating device includes: a rotating body; a heating body as defined herein; and a contact mechanism, in a non-existence state where a material to be heated does not exist between the rotating body and the heating body after the material to be heated passes between the rotating body and the heating body, configured to cause the rotating body to be in contact with the heating body at a central portion of the rotating body in a rotation axis direction of the rotating body, so that an area of the rotating body in contact with the heating body is smaller at each of both end portions of the rotating body than at the central portion of the rotating body in the rotation axis direction, or configured to switch the rotating body between a first contact state and a second contact state as defined herein.

A fixing apparatus includes a fixing belt, a heating roller, a nip portion forming member, a pressing rotary member, a suspending roller, and an urging unit. The heating roller is in contact with an inner surface of the fixing belt and heats the fixing belt. The suspending roller has a center and both ends in an area where the fixing belt and the suspending roller are in contact with each other in a width direction of the suspending roller. Outside diameters at both ends are greater than an outside diameter at the suspending roller center by a value between 50 micrometer and 300 micrometer, inclusive. The urging unit urges the suspending roller from the inner surface of the fixing belt toward an outer circumference surface of the fixing belt. A force that the urging unit applies to the suspending roller ranges between 50 newtons and 100 newtons, inclusive.

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 device includes a fixing rotator, a pressure rotator, a pressure plate, a pressing force adjuster, an entrance guide, an exit guide, and a guide. The pressure rotator presses the fixing rotator to form a nip between the fixing rotator and the pressure rotator. The pressure plate rotates about a fulcrum to press the pressure rotator. The pressing force adjuster adjusts a pressing force of the pressure rotator. The entrance guide guides a recording medium entering the nip. The exit guide guides the recording medium ejected from the nip. The guide guides the pressure rotator in a direction inclined from a line connecting a rotation center of the fixing rotator and a rotation center of the pressure rotator toward downstream in a conveyance direction of the recording medium.

A fixing apparatus includes a guide member that guides a rotating member. The guide member has a contact surface that restricts a position of the guide member with respect to a stay by coming into contact with a surface of the stay on the upstream side in a printing-material conveying direction. The contact surface is disposed, in a direction perpendicular to the printing-material conveying direction, in such a manner that a center is downstream from ends in the printing-material conveying direction.

A fuser includes a pressure pad forming a nip with a fuser belt between the pad and a fuser rotator. A pressure face in contact with the belt has profiles in planes normal to the axis of the rotator. The profiles each include a reference section, the first to come into contact with the rotator with the belt in between when the pad forms the nip, and a boundary section at a threshold distance from the reference section in the width direction of the nip. When the pad is apart from the nip due to removal of a force applied by a pusher unit, the boundary section is, relative to the reference section, more largely displaced in the opposite direction to that of the rotator in one of the profiles located at a larger distance from a center portion of the pad in the axial direction of the rotator.

A fixing apparatus includes a fixing belt, a heating roller, a nip portion forming member, a pressing rotary member, a suspending roller, and an urging unit. The heating roller is in contact with an inner surface of the fixing belt and heats the fixing belt. The suspending roller has a center and both ends in an area where the fixing belt and the suspending roller are in contact with each other in a width direction of the suspending roller. Outside diameters at both ends are greater than an outside diameter at the suspending roller center by a value between 50 micrometer and 300 micrometer, inclusive. The urging unit urges the suspending roller from the inner surface of the fixing belt toward an outer circumference surface of the fixing belt. A force that the urging unit applies to the suspending roller ranges between 50 newtons and 100 newtons, inclusive.

A fixing device includes a first pressing member, a fixing belt, a second pressing member, a tensioning section on which the fixing belt is wound on an upstream side relative to the fixing nip in a rotation direction of the fixing belt and which is configured to impart tension to the fixing belt, and a control section configured to control the tensioning section such that the shape in an axial direction of the fixing belt is changed in accordance with a type of sheet which passes through the fixing nip.