A medium transporting apparatus includes a transport belt that has a loop shaped, a cling mechanism that causes the medium to cling to the transport belt, a rotation mechanism that transports the medium by rotating the transport belt, a plurality of detection units that detect an transport direction end of the medium, a controller that corrects a skew of the medium, and a stacker on which the medium transported by the transport belt is stacked, in which the plurality of detection units are arranged at positions that are on an upstream side of the transport belt in the first transport direction and that are different from each other in a width direction, and the controller corrects, according to a result of the detection by the detection units, the skew of the medium in a state of being cling to the transport belt.

According to an example, an apparatus to prevent media transport jams may include an actuator to load and advance a media within a media path width. The apparatus may also include a first sensor and a second sensor to detect respective edges of the media, in which the first sensor and the second sensor may be positioned outside of a media action area and on opposite sides of the media path width. The apparatus may further include a controller to prevent the actuator from advancing the media along the media path in response to a detection of one or both of the first edge of the media by the first sensor and the second edge of the media by the second sensor.

According to an example, an apparatus to prevent media transport jams may include an actuator to load and advance a media within a media path width. The apparatus may also include a first sensor and a second sensor to detect respective edges of the media, in which the first sensor and the second sensor may be positioned outside of a media action area and on opposite sides of the media path width. The apparatus may further include a controller to prevent the actuator from advancing the media along the media path in response to a detection of one or both of the first edge of the media by the first sensor and the second edge of the media by the second sensor.

A sheet conveying device, which is included in an image forming apparatus and a post processing device, includes multiple position detectors and a position corrector. The multiple position detectors are aligned along a sheet conveying direction and configured to detect a side end of a sheet. The position corrector is configured to convey the sheet and correct a position of the sheet based on a positional deviation amount of the sheet, obtained by a detection result of the multiple position detectors. The positional deviation amount of the sheet is obtained by an extreme downstream position detector in the sheet conveying direction, of the multiple position detectors. A position of a subsequent sheet is corrected based on a sum of the positional deviation amount of the sheet and a positional deviation amount of the subsequent sheet.

An image forming apparatus includes: an image forming part that forms an image on a sheet conveyed in a conveying path; a transfer part that transfers the image; a conveying roller that is arranged at the upstream of the transfer part in the conveying path, has rollers, and conveys the sheet to the transfer part; roller drive mechanisms that independently rotate the rollers; a first bend detection sensor that is arranged in the conveying path and detects a bend of a front end of the sheet relative to the conveying direction; a sheet rotation angle calculation part that calculates a first rotation offset angle of the front end of the sheet relative to an axial line of the conveying roller; a roller driving amount calculation part that calculates the driving amounts of the roller drive mechanisms; and a drive mechanism control part that controls operations of the roller drive mechanisms.

An image forming apparatus includes: an image forming part that forms an image on a sheet conveyed in a conveying path; a transfer part that transfers the image; a conveying roller that is arranged at the upstream of the transfer part in the conveying path, has rollers, and conveys the sheet to the transfer part; roller drive mechanisms that independently rotate the rollers; a first bend detection sensor that is arranged in the conveying path and detects a bend of a front end of the sheet relative to the conveying direction; a sheet rotation angle calculation part that calculates a first rotation offset angle of the front end of the sheet relative to an axial line of the conveying roller; a roller driving amount calculation part that calculates the driving amounts of the roller drive mechanisms; and a drive mechanism control part that controls operations of the roller drive mechanisms.

A medium feeding device includes an imaging unit which images a medium tip end portion from a position of facing a face of the medium on a downstream side of a nipping position of the medium using a feeding unit and a separating unit; and a determining unit which determines whether or not there is transport disorder by evaluating a state of a boundary between a path member which forms a medium transport path and a medium tip end from image data obtained by the imaging unit, in which the determining unit sets a rectangular determining region including at least a part of the boundary with respect to the image data, and determines whether or not there is transport disorder based on a length of a boundary in the determining region.

A medium feeding device includes an imaging unit which images a medium tip end portion from a position of facing a face of the medium on a downstream side of a nipping position of the medium using a feeding unit and a separating unit; and a determining unit which determines whether or not there is transport disorder by evaluating a state of a boundary between a path member which forms a medium transport path and a medium tip end from image data obtained by the imaging unit, in which the determining unit sets a rectangular determining region including at least a part of the boundary with respect to the image data, and determines whether or not there is transport disorder based on a length of a boundary in the determining region.

An image-forming apparatus that is capable of accurately detecting skew angle when arriving at a resist roller. In the image-forming apparatus, the resist roller feeds the printing paper to a printing unit at specified timing, and the printing unit performs printing on the printing paper. The flat-conveying section is formed between the paper-supply roller and the resist roller, and conveys the paper in a flat state. The camera takes images of the edge of the front end of the printing paper that is conveyed in the flat-conveying section. The camera-driving apparatus causes the camera to move along the flat-conveying section at the designed conveying speed of the printing paper. The skew-detection unit, based on images taken in the flat-conveying section by the camera, detects the skew angle when arriving at the resist roller as the arrival skew angle.

An image-forming apparatus that is capable of accurately detecting skew angle when arriving at a resist roller. In the image-forming apparatus, the resist roller feeds the printing paper to a printing unit at specified timing, and the printing unit performs printing on the printing paper. The flat-conveying section is formed between the paper-supply roller and the resist roller, and conveys the paper in a flat state. The camera takes images of the edge of the front end of the printing paper that is conveyed in the flat-conveying section. The camera-driving apparatus causes the camera to move along the flat-conveying section at the designed conveying speed of the printing paper. The skew-detection unit, based on images taken in the flat-conveying section by the camera, detects the skew angle when arriving at the resist roller as the arrival skew angle.