An image reading apparatus includes a stacking unit, a conveyance unit to convey stacked sheets, a reading unit, a white reference plate provided in a second position, and a processor. The reading unit is movable and, at a first position, reads a conveyed sheet image to obtain image data and, at the second position, reads the white reference plate. The processor generates, based on a plate reading result, a shading correction value and corrects the image data using the shading correction value. Based on whether the number of times in which reading the white reference plate has been performed is less than a predetermined number of times, the reading unit changes a time interval in a reading period that is from a first timing to a second timing. The processor generates, each time the white reference plate is read, the shading correction value based on the plate reading results.

Some examples of a document scanning system can include a scanner and a sheet output stacker. The stacker includes an upper surface configured to mate with the scanner configured to scan and transfer contents of a paper document. The stacker is configured to receive paper sheets from the scanner. The stacker includes multiple, upward extending interface housings positioned on the upper surface. The multiple interface housings are configured to be received in respective multiple receiving structures in the scanner, and are configured to mechanically and electrically couple the sheet output stacker and the scanner. The interface housings allow care-free electrical and mechanical pairing of a scanner to a stacker with no tools or adjustments. Simply positioning the scanner on the stacker such that the interface housings are aligned with the receiving structures results in the scanner being automatically guided into place and connected to the stacker through gravity.

A sheet stacking tray includes a first conveyor, a second conveyor, a sheet stopper, a first full-load detector, a second full-load detector, and a plurality of motors. The plurality of motors maintain the sheet stopper at a protruding position to block a sheet conveyed by the first conveyor until the first full-load detector outputs a signal indicating that a sheet bundle is fully loaded, shift the sheet stopper to a lowered position to allow the sheet bundle to pass when the first full-load detector outputs the signal indicating that the sheet bundle is fully loaded, drive the first conveyor and the second conveyor together to convey the sheet bundle when the sheet stopper shifts to the lowered position, and stop the second conveyor and drive only the first conveyor, when the second full-load detector detects a leading edge of the sheet bundle.

A medium-discharging device includes: a device main body including a medium-discharging section that discharges a medium; a medium-receiving tray that receives the medium discharged by the medium-discharging section; and a pressing member that is configured to be attached to and detached from to the device main body and presses the medium discharged by the medium-discharging section against the medium-receiving tray in a state in which the pressing member is attached to the device main body, in which the pressing member is configured to switch, in the state in which the pressing member is attached to the device main body, between a first state in which the pressing member comes into contact with the medium-receiving tray and a second state in which the pressing member retreats upward so as to be apart from the medium-receiving tray.

An image forming apparatus includes a printer portion; an image reading portion rotatable relative to the printer portion; a discharge portion configured to stack the recording material discharged from an inside of the printer portion, the discharge portion being supported rotatably relative to the printer portion; and a regulating member provided between the discharge portion and the image reading portion and configured to regulate movement of the recording material stacked on the discharge portion. When the image forming apparatus is seen in a rotational axis direction of the image reading portion, at least a part of the regulating member in a state in which the image reading portion and the discharge portion are open away from the printer portion is hidden inside a contour of a casing of the image reading portion.

A sheet stacking tray includes a first conveyor, a second conveyor, a sheet stopper, a first full-load detector, a second full-load detector, and a plurality of motors. The plurality of motors maintain the sheet stopper at a protruding position to block a sheet conveyed by the first conveyor until the first full-load detector outputs a signal indicating that a sheet bundle is fully loaded, shift the sheet stopper to a lowered position to allow the sheet bundle to pass when the first full-load detector outputs the signal indicating that the sheet bundle is fully loaded, drive the first conveyor and the second conveyor together to convey the sheet bundle when the sheet stopper shifts to the lowered position, and stop the second conveyor and drive only the first conveyor, when the second full-load detector detects a leading edge of the sheet bundle.

A motor control unit controls a driving current that flows through a coil of a motor to be driven, by controlling a PWM signal supplied to an H bridge circuit constituted by FETs. A current value generation unit detects a driving current based on a voltage that occurs across a current detection resistor, and corrects a detection value by using a first or second correction value. The current value generation unit, if the driving current is detected in the H period of the PWM signal, corrects the detection value by using the first correction value, and if the driving current is detected in the L period of the PWM signal, corrects the detection value by using the second correction value that has a polarity different from a polarity of the first correction value.

A recording apparatus includes an apparatus body, a recording section configured to perform recording on a medium, a support tray configured to support the medium on which recording was performed, and a light emitter configured to illuminate a portion of the support tray exposed to the outside of the apparatus body.

A first surface of a first sheet has a second image formed in advance. An image forming system generates reference data based on a result of reading an image on the first surface of the first sheet on which a first image is not formed, generates first image data that represents a result of reading an image on the first surface of the first sheet having the first image formed on the first surface, and determines, based on the reference data and the first image data, a relative position between the first image and the second image on the first surface of the first sheet.

An image forming system includes an image forming apparatus and an image reading apparatus. The image forming apparatus includes an image forming unit, a first pair of conveying rollers and a first motor driving the first pair of conveying rollers at a first speed. The image reading apparatus includes an image reading unit, a second pair of conveying rollers arranged downstream of said first pair of conveying rollers and a second motor driving the second pair of conveying rollers at a second speed lower than the first speed. The second motor drives the second pair of conveying rollers at the second speed so as to form a loop of the sheet between the first pair of conveying rollers and the second pair of conveying rollers.