An image forming apparatus includes an image forming unit, a fixing unit including a tubular film and an opposed member to form a first nip, a conveying unit including a second nip, the pressure variable mechanism changing a pressure of the second nip, a control unit controlling the pressure variable mechanism, and an acquisition unit acquiring information about a length of the recording material. The control unit controls the pressure variable mechanism according to the information so that the recording material is conveyed by the second nip set to a first pressure when the length of the recording material is less than a predetermined length, and the recording material is conveyed by the second nip set to a second pressure lower than the first pressure when the length of the recording material is equal to or greater than the predetermined length.

A paper humidifying apparatus includes humidifying rollers, a first drive unit and a controller. The humidifying rollers, forming a pair, are pressed against each other forming a nip portion and apply moisture to a sheet of paper when sandwiching and conveying the sheet of paper. The first drive unit which makes the humidifying rollers separate from each other or press against each other. The controller controls the first drive unit. The controller controls the first drive unit so as to make the humidifying rollers separate from each other and receive the sheet of paper, and after a tip of the sheet of paper passes a position corresponding to the nip portion, the controller controls the first drive unit so as to make the humidifying rollers press against each other to apply moisture to the sheet of paper.

A post-processing device is provided with a post-processing unit which performs post-processing of a recording medium on which recording is performed, a transport path through which the recording medium is transported, or a deformation suppressing unit which suppresses deformation of the recording medium on a mounting unit on which the recording medium is mounted, in which the deformation suppressing unit is controlled based on a predetermined parameter related to recording processing with respect to the recording medium.

There is provided a post processing device including a mounting portion on which a medium is temporarily mounted, a post processing unit that performs post processing on the medium mounted on the mounting portion, a discharging tray on which the medium is stacked after being discharged, and a suppressing unit that suppresses deformation of the medium mounted on the mounting portion.

A paper delivery device includes a shift frame movable in a second direction perpendicular or substantially perpendicular to a first direction along which paper is delivered to outside, a driver that moves the shift frame in the second direction, a drive roller with a first outer peripheral surface extending in the second direction and supported by the shift frame such that the drive roller is rotatable about a first shaft parallel or substantially parallel to the second direction, a first driven roller with a second outer peripheral surface extending in the second direction and contactable with the first outer peripheral surface at a first contact position, the first driven roller supported by the shift frame such that the first driven roller is rotatable about a second shaft parallel or substantially parallel to the second direction following the rotation of the drive roller, the first driven roller being rotated in a state where the paper is nipped between the first outer peripheral surface and the second outer peripheral surface thus transporting the paper in the first direction, and a second driven roller with a third outer peripheral surface extending in the second direction and contactable with the first outer peripheral surface at a second contact position downstream of the first contact position in the first direction, the second driven roller being supported by the shift frame such that the second driven roller is rotated about a third shaft disposed parallel or substantially parallel to the second direction following the rotation of the drive roller, the second driven roller being rotated in a state where the paper which is nipped between the first outer peripheral surface and the second outer peripheral surface is nipped by the first outer peripheral surface and the third outer peripheral surface thus transporting the paper in the first direction.

An image forming apparatus includes: a conveyance section configured to convey a sheet in a direction opposite to a first conveyance direction during image formation, the direction being a second conveyance direction; and a distortion correction section disposed on an upstream side of a transfer nip in the first conveyance direction and configured to correct, when the sheet is conveyed by the conveyance section in the second conveyance direction, distortion of the sheet generated when the sheet passes through a fixing nip.

A sheet cooling apparatus cools a sheet while conveying the sheet having passed through a fixing device for fixing an unfixed toner image formed on the sheet by heating the toner image. A second suspension member is arranged so as to press a second endless belt on a circumferential face of a first cooling roller through a first endless belt, a first suspension member is arranged so as to press the first endless belt on a circumferential face of a second cooling roller through the second endless belt, and a curved sheet conveying path is formed between the first endless belt and the second endless belt.

A paper delivery device includes a shift frame movable in a second direction perpendicular or substantially perpendicular to a first direction along which paper is delivered to outside, a driver that moves the shift frame in the second direction, a drive roller with a first outer peripheral surface extending in the second direction and supported by the shift frame such that the drive roller is rotatable about a first shaft parallel or substantially parallel to the second direction, a first driven roller with a second outer peripheral surface extending in the second direction and contactable with the first outer peripheral surface at a first contact position, the first driven roller supported by the shift frame such that the first driven roller is rotatable about a second shaft parallel or substantially parallel to the second direction following the rotation of the drive roller, the first driven roller being rotated in a state where the paper is nipped between the first outer peripheral surface and the second outer peripheral surface thus transporting the paper in the first direction, and a second driven roller with a third outer peripheral surface extending in the second direction and contactable with the first outer peripheral surface at a second contact position downstream of the first contact position in the first direction, the second driven roller being supported by the shift frame such that the second driven roller is rotated about a third shaft disposed parallel or substantially parallel to the second direction following the rotation of the drive roller, the second driven roller being rotated in a state where the paper which is nipped between the first outer peripheral surface and the second outer peripheral surface is nipped by the first outer peripheral surface and the third outer peripheral surface thus transporting the paper in the first direction.

An image forming apparatus has a fixing unit including a first fixing member and a second fixing member opposing to the first fixing member, a curl correcting unit including a first curl correcting member and a second curl correcting member opposing to the first curl correcting member, a first changing member rotatable about a first rotation center, the first changing member changing a pressure to the sheet by the first fixing member and the second fixing member, and a second changing member rotatable about the first rotation center, the second changing member changing a pressure to the sheet by the first curl correcting member and the second curl correcting member.

The curl correction device includes a first guide that guides a sheet to a nip portion between a first rotation member and a second rotation member, a support portion that rotatably supports the first guide about a fulcrum on the downstream side of the first guide, and a restriction portion that restricts a rotation of the first guide rotating about the fulcrum by being in contact with the first guide. The first guide is rotatable about the fulcrum so as to become separated from the restriction portion.