An image reading device includes a plurality of conveyance rollers to convey a sheet, a motor to drive the plurality of conveyance rollers, an image reading unit to read an image of the sheet, a control device to perform a stop control that stops the sheet in a course of a conveyance path, and a clutch to transmit a driving force of the motor. A first conveyance roller group includes at least one of the plurality of conveyance rollers upstream from a leading end of the sheet stopped by the stop control in a conveyance direction, to which the driving force is transmitted via the clutch. A second conveyance roller group includes at least one of the plurality of conveyance rollers downstream from the leading end of the sheet stopped by the stop control in the conveyance direction, to which the driving force is transmitted without the clutch.

An image reading device includes: a reading unit; a first detecting unit that detects a position of the reading unit in the sub-scanning direction; a second detecting unit that detects a position of the reading unit in the sub-scanning direction; and a calculating unit that calculates a skew quantity and a skew direction of the reading unit, based on a difference, introduced by the skew, between a travel distance by which the reading unit has travelled from a measurement reference position located on an upstream side of the first detecting unit and the second detecting unit in a moving direction to a point where the reading unit is detected by the first detecting unit, and a travel distance by which the reading unit has travelled from the measurement reference position to a point where the reading unit is detected by the second detecting unit.

An image reading apparatus includes a pair of first detection sections disposed between first positions for the feeding rollers and the separation rollers for nipping and second positions for the transport roller pair for nipping, and a pair of second detection sections disposed between the first detection sections and the second positions in the medium transport direction. The second detection sections are disposed between the first detection sections in the medium width direction, and a controller determines whether to stop transporting the medium or continue transporting the medium based on the results of detection by the first detection sections and the second detection sections.

According to examples, an apparatus may include a processor and a memory on which are stored computer-readable instructions that, when executed by the processor, may cause the processor to identify first property values along an image of a pattern. The first property values may be identified based on a first signal corresponding to an image of the pattern captured by an imaging sensor. The pattern may be positioned at a spaced relation with respect to the imaging sensor. The processor may receive a second signal corresponding to a second image captured by the imaging sensor, and may identify, from the second signal, second property values along the second image. Based on a determination that the second property values differ from the first property values, the processor may determine that a beginning of a media is positioned to be imaged by the imaging sensor.

An image processing apparatus includes a memory, a correction circuit, and a calculation circuit. The memory stores image data of an original image that is moved in a sub-scanning direction with respect to an image sensor. The correction circuit sequentially reads the image data from the memory line by line in the main scanning direction, extracts a pixel in a position corresponding to the inclination, and forms an inclination-corrected line in the main scanning direction to correct the inclination. The calculation circuit calculates an amount of movement of a corner of the original image with respect to the sub-scanning direction before and after correction of inclination of the original image with respect to a main scanning direction. The correction circuit restricts progress of formation of the inclination-corrected line based on the amount of movement. The amount of movement is applied when the inclination of the original image is corrected.

A sheet conveying apparatus includes a second conveying roller adjoining a motor driven first conveying roller, a phase determiner to determine a rotational phase of a rotor of the motor, a controller, and a discriminator. The controller controls a drive current flowing through a winding of the motor to reduce phase deviation. The discriminator executes a discrimination regarding one of whether a front end of a sheet has reached a nip portion and whether a rear end of the sheet has passed through a nip portion. The controller controls such that the first conveying roller rotates at a first conveying roller peripheral velocity which is different from a peripheral velocity of the second conveying roller. The discriminator executes the discrimination based on a value of a parameter corresponding to a load torque applied to the rotor where the first conveying roller rotates at the first conveying roller peripheral velocity.

An image reading apparatus including a controller configured to perform an update processing for updating shading correction data stored in a memory by a generation processing of generating shading correction data based on an image signal of a reference member and perform a size determination processing for determining a size of a document based on an image signal of the document, wherein, when the document on the document platen is read, the controller performs the generation processing before the document is read, and an image processing portion performs the shading correction using the shading correction data generated before the document is read, and wherein, when the size determination processing is performed, the image processing portion performs the shading correction using the shading correction data stored in the memory, and the update processing is not performed.

An image reading apparatus is configured to read an image of each of documents transported in a transport path from an upstream side to a downstream side in a transport direction, acquires a correction factor for correcting a read image on the basis of a fed document number, and corrects the length of the read image in the transport direction on the basis of the correction factor which has been acquired.

When a multi-feed of a document is detected, an image reading device acquires a document width from image data generated by a reading unit reading a leading end portion of the document. The document width is a length of the document in a width direction intersecting a transport direction. When, based on the document width, the size of the document corresponds to a specific size of a plastic card or an instant film, the image reading device does not execute error processing in response to an occurrence of the multi-feed, and when the size of the document does not correspond to the specific size, the image reading device executes the error processing.

A method and apparatus for processing documents is provided. The documents may be conveyed to a feeder for feeding documents to a scanner. The scanner scans each document to obtain image data and then discharges the document to one or more output or sort locations. The system may include a skew reduction assembly for reducing skew in the documents as the documents are fed to the scanner. The system may also include elements for improving image quality and reducing document damage while the document is scanned. The system may further include features for improving the stacking of the discharged documents.