A pinch roller mechanism includes a rail, a slider, a roller bracket, a spring, and a pinch roller. The rail extends in a first direction crossing the conveyance direction of a medium while being apart from a medium driving roller configured to convey the medium. The slider is supported by the rail to be movable along the rail. The roller bracket is supported by the slider to be movable with respect to the medium driving roller. The spring is provided between the slider and the roller bracket and biases the roller bracket toward the medium driving roller. The pinch roller is rotatably supported by the roller bracket while setting the axial direction in the first direction.

An image forming apparatus includes an image forming portion, an oblique movement correcting portion including a first registration roller pair and a first moving portion, a reversing portion, and a re-feeding portion. The reversing portion includes a reversing roller pair and a second moving portion. The re-feeding portion includes a second registration roller pair. When an image is formed on a second surface of a sheet opposite from a first surface of the sheet, a side end position of the sheet is corrected by the second moving portion and oblique movement of the sheet is corrected, and then the side end position of the sheet is corrected again by the first moving means and the sheet is fed to the image forming portion.

In order to properly suppress a discharge defect corresponding to an image ratio of a sheet, in the case where a coefficient of friction is different according to the image ratio of an image on the sheet, an air blowing section is arranged to blow air toward a downstream side in a transport direction from between a downstream-side end portion of a first stacking section and an upstream-side end portion of a second stacking section. When an image ratio of an image on a sheet by an image forming apparatus is a first value, the air blowing section sets an air quantity blown to the sheet at a first air quantity F1, while when the image ratio is a second value higher than the first value, setting the air quantity blown to the sheet at a second air quantity F2 larger than the first air quantity F1.

A sheet conveying device includable in an image forming apparatus that uses a method of conveying a conveyance target medium and a method of forming an image, includes a position detector, a position adjuster, and circuitry. The position detector is configured to detect a position of a conveyance target medium. Based on a detection of the position of the conveyance target medium by the position detector, the position adjuster moves in at least one of a width direction of the conveyance target medium and a rotation direction of the conveyance target medium within a plane of conveyance of the conveyance target medium and repeatedly adjusts the position of the conveyance target medium while conveying the conveyance target medium. The circuitry changes a conveying speed of the conveyance target medium, according to a change of the position of the conveyance target medium after adjusted by the position adjuster.

A sheet discharge device includes at least one sheet discharge tray, a sheet discharge position adjustment actuator, and a controller. The sheet discharge tray receives discharged sheets. The discharge position adjustment actuator adjusts discharge positions of the discharged sheets on the at least one sheet discharge tray. The controller compares a first rotation amount of first print data printed on a first sheet with a second rotation amount of second print data printed on a second sheet. In response to a determination that the first rotation amount is different than the second rotation amount, the controller controls the sheet discharge position adjustment actuator to (a) discharge the first sheet to a first discharge position and (b) discharge the second sheet to a second discharge position different than the first discharge position.

A medium conveyance device includes: a plurality of roller pairs arranged in a width direction of a recording medium, the plurality of roller pairs including at least two end-side roller pairs respectively located near two ends of the recording medium in the width direction and at least one center-side roller pair located near a center of the recording medium in the width direction, the plurality of roller pairs each including a pair of rollers that convey the recording medium while nipping the recording medium and are individually contactable with and separable from each other; and a contact and separation mechanism that moves a first roller of the pair of rollers of the at least one center-side roller pair in a thickness direction of the recording medium or moves a first roller of the pair of rollers of each of the at least two end-side roller pairs in the thickness direction of the recording medium, to make a difference in separation timing.

A sheet conveyance apparatus includes a first conveyance path, a detection portion, a second conveyance path, a discharge unit, and a controller. The discharge unit is movable in a width direction and is configured to perform a discharge operation of discharging a sheet onto a first discharge portion and a reversing operation of reversing and conveying the sheet to the second conveyance path. The controller is configured to control the discharge unit and to execute a first alignment control when the reversing operation is performed. The first alignment control is a control in which the discharge unit moves the sheet in the width direction based on a position of the sheet detected by the detection portion to align the sheet at a target position.

A sheet feeding device includes a first feeding roller pair, a reference member, an obliquely feeding roller, a second feeding roller pair, a detecting portion, and a controller. Before a sheet is obliquely fed by the obliquely feeding roller, the controller causes the first feeding roller to move the sheet to a predetermined position in a widthwise direction of the sheet on the basis of a detection result of the detecting means.

A sheet transport device includes a pair of movable transport rollers capable of transporting a sheet while holding the sheet and moving in an axial direction crossing a transportation direction; pairs of first transport rollers upstream from the pair of movable transport rollers in the transportation direction while being spaced apart from each other to transport the sheet while holding the sheet; and pairs of transport guides to define sheet transport spaces between the pair of movable transport rollers and the pairs of first transport rollers and between the pairs of first transport rollers. When the pair of movable transport rollers is to be moved in the axial direction, at least one pair of first transport rollers transports the sheet while bending the sheet in the transport space by producing a difference in transport rate within a portion of a section upstream from the pair of movable transport rollers.

A sheet transport device includes a pair of movable transport rollers capable of transporting a sheet while holding the sheet and capable of moving in an axial direction crossing a transportation direction; pairs of first transport rollers disposed at a distance from each other upstream from the pair of movable transport rollers in the transportation direction to transport the sheet while holding the sheet; and pairs of first transport guides disposed to define sheet transport spaces between the pair of movable transport rollers and the pairs of first transport rollers and between the pairs of first transport rollers. When the pair of movable transport rollers is moved in the axial direction, at least one of the pairs of first transport rollers is displaced in a direction to widen the transport space.