According to one embodiment, an image forming apparatus includes a conveying roller to convey sheets of different types along a conveyance path, a first sensor to detect a sheet being conveyed at a first position, a second sensor to detect the sheet being conveyed at a second position that is at a fixed distance downstream of the first position, a registration roller pair that is downstream of the second sensor, and a control unit. The control unit calculates a transit time for the sheet between the first position and the second position according detection results from the first and second sensors, and then sets a conveying distance for the sheet after the second position to be used for aligning the sheet against the registration roller pair based on the calculated transit time of the sheet.

An image reading device includes a tray, a paper feed roller that conveys a sheet, a first sensor that detects a front end and a rear end of the sheet, a second sensor that detects the front end of the sheet, and a scanner that reads an image on a front side of the sheet and reads an image on a back side of the sheet. A controller determines a first time duration that elapses from the detection of the front end of the sheet by the first sensor to the detection of the rear end of the sheet by the first sensor and operates the scanner to read the image on the back side of the sheet over a second time duration equal in length to the first time duration. The second time duration begins after the front end of the sheet is detected by the second sensor.

An image reading device includes a tray, a paper feed roller that conveys a sheet, a first sensor that detects a front end and a rear end of the sheet, a second sensor that detects the front end of the sheet, and a scanner that reads an image on a front side of the sheet and reads an image on a back side of the sheet. A controller determines a first time duration that elapses from the detection of the front end of the sheet by the first sensor to the detection of the rear end of the sheet by the first sensor and operates the scanner to read the image on the back side of the sheet over a second time duration equal in length to the first time duration. The second time duration begins after the front end of the sheet is detected by the second sensor.

In a case where a recording medium is to be stopped on a conveyance path and a length of the recording medium is a first length, a first controller stops a first motor upon a sensor detecting the front end of the recording medium, and a second controller stops a second motor upon the sensor detecting the front end of the recording medium. In a case where the recording medium is to be stopped on the conveyance path and the length of the recording medium is a second length, the first controller stops the first motor upon the sensor detecting the front end of the recording medium, and the second controller continues driving of the second motor even if the sensor detects the front end of the recording medium.

An image reading apparatus includes a transport section that can transport original documents along a transport path, a reading section configured to read images of the original documents transported by the transport section, an output controller configured to output data of the original documents read by the reading section, a multi-sheet feed detection sensor configured to detect a multi-sheet feed of the original documents transported by the transport section, and an instruction section configured to issue an instruction to disable multi-sheet feed detection by the multi-sheet feed detection section.

Printers capable of determining a media type of a media and associated methods are provided. An example method includes scanning a media with a verifier associated with the printer to generate at least two consecutive windows of the media. The example method further includes determining a vertical length of a captured image based on a comparison of image characteristic values captured in the at least two consecutive windows. The example method further includes determining a media characteristic associated with the media based at least on the captured image and the vertical length and one or more stored media profiles. The example method further includes calibrating the printer based on the media characteristic.

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.

A document feeder includes an apparatus body to which a document feed unit is attached, a sheet feed tray that moves up and down toward the document feed unit, an open/close cover attached openably and closably to the apparatus body and opens the document transport path and the document feed unit when opened, and a unit pressing arm attached to the open/close cover. When the open/close cover is closed, the unit pressing arm presses the document feed unit toward the sheet feed tray.

An image reading apparatus includes a reading unit having a plurality of light receiving elements arranged in a main scanning direction and configured to read an original placed on an original platen, a moving portion configured to move the reading unit in a sub-scanning direction, an edge extractor configured to extract original edges from image data of an original pressure plate and the original read by the reading unit, a determiner configured to determine, from the original edges, an angle of an original leading edge with respect to the main scanning direction and position information of one end of the original leading edge, a controller configured to terminate a movement of the reading unit when an original trailing edge end point is extracted from the original edges, and a rotation correction unit configured to correct a rotation of the image data based on the angle and the position information.

The image reading apparatus includes a separation roller, an imaging device to generate an input image, a conveyance roller to convey the medium separated by the separation roller to the imaging device, a first medium sensor located between the separation roller and the conveyance roller, a second medium sensor located between the conveyance roller and the imaging device, a processor to start imaging by the imaging device in response to detection of the medium by the first medium sensor and generate a cutout image from the input image in response to detection of the medium by the second medium sensor, and an output device to output the cutout image. The processor generates the cutout image based on a position imaged by a predetermined amount before a position imaged at a timing when the second medium sensor detects the medium, in the input image.