A sensor unit includes an edge detection sensor, a sensor carriage, a unit housing, and a carriage moving mechanism. The edge detection sensor is arranged in a conveying portion for conveying a sheet and senses edge positions at both sides in a sheet width direction perpendicular to a sheet conveying direction. The sensor carriage has a carriage main body in which the edge detection sensor is incorporated, and is reciprocatably supported on the unit housing in the sheet width direction. The carriage moving mechanism makes the sensor carriage reciprocate in the sheet width direction. The sensor carriage is selectively positioned at a first position where it makes contact with a first side face at one end side of the unit housing in the sheet width direction or a second position where it makes contact with a second side face at the other end side in the sheet width direction.

A sheet conveying device includes a detector configured to detect an attitude of a conveyance target medium, a corrector configured to perform a correcting operation based on a detection result of the detector, and circuitry configured to calculate an angular displacement correction amount and a lateral displacement correction amount of the conveyance target medium, cause the corrector to perform the correcting operation in a direction perpendicular to a sheet conveying direction, based on the lateral displacement correction amount, after the corrector grips the conveyance target medium, and cause the corrector to rotate by the angular displacement correction amount of the conveyance target medium before the corrector grips the conveyance target medium and to perform the correcting operation in a direction of rotation of the conveyance target medium, based on the angular displacement correction amount, after the corrector grips the conveyance target medium.

An automatic document feeding system includes an image reader including an optical window and a light source illuminating the optical window, and an automatic document feeder including a reflective flag positioned within a viewing region of the optical window.

An image forming apparatus includes an image forming unit configured to perform a printing process of forming an image on a print medium based on print data, and a processor. The processor is configured to determine whether or not the printing process has completed based on remaining print data to be printed, when the print medium is removed from a paper discharge tray in which the print medium on which the image is formed by the image forming unit is placed, and to cause a warning to be output upon determining that the printing process has not completed based on the remaining print data to be printed.

An ultrasonic sensor includes a transmission unit that is disposed on a first axis which is inclined with respect to a normal line of a surface of an object, a reception unit that is provided on a side opposite to the transmission unit of the object, on the first axis, and a transmission control unit that controls drive of the transmission unit. The transmission unit includes a plurality of transmission elements that transmit ultrasonic waves, and the plurality of transmission elements are arranged in a first direction that intersects the first axis in a plane including the normal line and the first axis. The transmission control unit delay-drives the plurality of transmission elements to align a direction of the ultrasonic wave that is transmitted from the transmission unit with the first axis.

A sheet conveying apparatus includes a controller to set conveyance speeds of first, second, and third conveyance rotary members. The controller sets the conveyance speed of a sheet by the second conveyance rotary member to a first conveyance speed, which is the same as a conveyance speed of the sheet by the first conveyance rotary member, and a second conveyance speed which is different from the first conveyance speed. When the controller sets the conveyance speed of the sheet by the first conveyance rotary member to the first conveyance speed and sets the conveyance speed of the sheet by the second conveyance rotary member to the second conveyance speed, the controller sets the conveyance speed of the sheet by the third conveyance rotary member to a third conveyance speed which is a speed between the first conveyance speed and the second conveyance speed.

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 paper warping detection device includes an input tray, a processor, a first emitting element, a first receiving element and a first analog-to-digital converter. A first critical value is stored in the processor. The first emitting element is electrically connected with the processor. The first receiving element is disposed to the other side of the input tray. The first receiving element and the first emitting element face each other. When the first emitting element is switched on, the first emitting element emits first ultrasonic wave signals towards the first receiving element. The first analog-to-digital converter is electrically connected with the first receiving element and the processor for converting the first ultrasonic wave signals into first digital signals and outputting the first digital signals to the processor. The processor reads the first digital signals and compares the first digital signals with the first critical value.

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 reading apparatus includes a feeding roller that includes a first roller and a second roller provided at an interval in a width direction intersecting a medium feeding direction, and feeds a sheet from a placing section; and a skew detection section that detects skew of the sheet fed from the feeding roller. Skew is corrected by giving a difference between a rotation speed of the first roller and a rotation speed of the second roller with respect to at least one of the relevant sheet detected by the skew detection section and subsequent sheets fed following the relevant sheet based on a skew amount in the sheet.