Abstract: An image forming apparatus which is capable of reading an original, temporarily storing image data in a storage unit, and then transferring the image data to an image forming unit to improve FCOT in forming an image. A memory stores image data output from image reading units. An image forming unit forms an image on a recording medium based on the image data stored in the memory. A first memory output frequency in a first mode in which one side of an original is read and an image is formed on one side of a recording medium is lower than a second memory output frequency in a second mode in which both sides of an original are read and an image is formed both sides of a recording medium.

Abstract: An image reading apparatus includes: a first size-detecting portion which detects a size of an original disposed on a disposing portion; a conveying portion which conveys the original disposed on the disposing portion to a reading portion, a second size-detecting portion which detects the size of the original to be conveyed by the conveying portion; a controller which calculates an overlap region between a reading region and an original region, with the reading region determined based on a reading size obtained by a obtain portion and the detection of the first size-detecting portion, and the original region determined by the second size-detecting portion; and a notifying portion which makes a predetermined notification based on the information that has been calculated.

Abstract: An image reading apparatus conveys a sheet of a sheet bundle on a document tray along a conveyance path one by one, reads images on the sheet and then, delivers the sheet to an output tray. By receiving driving force from a single driving source, each roller included in the image reading apparatus conveys the sheet along with the conveyance path in order. Each roller includes a feed roller, a separation roller, a conveyance roller, and a delivery roller. The reader included in the image reading apparatus obtains images on the sheet passing through the reading position which is set on the conveyance path.

Abstract: An original reading apparatus includes an original tray. A conveyance unit conveys an original of an original bundle on the original tray. A reading unit reads the original conveyed. A first detection unit detects a first length of the original in a principal scanning direction. A second detection unit detects a second length of the original bundle in an auxiliary scanning direction. A third detection unit detects the original conveyed. A prediction unit predicts an original size by selecting from candidates corresponding to the first length in a first prediction mode, or by determining based on the first and second lengths in a second prediction mode. A specifying unit specifies the original size based on the first length and a length in the auxiliary scanning direction detected by the third detection unit. A change unit changes the prediction mode when the predicted original size differs from the specified original size.

Abstract: An image reading apparatus allowing the user to easily sort, when early jam occurs and sheet conveyance is stopped, sheets already read and yet to be read. The image reading apparatus conveys sheet of the sheet bundle S placed on a document tray 30 along with the conveyance path one by one, reads images on the sheet and then, delivers the sheet to the delivery tray 31. By receiving driving force from a single driving source, each roller included in the image reading apparatus 400 conveys the sheet along with the conveyance path in order. Each roller includes feed roller 1, separation roller 2, conveyance roller 3, and delivery roller 5. The reader 200 included in the image reading apparatus 400 obtains images on the sheet passing through the reading position R which is set on the conveyance path P.

Abstract: An original reader capable of being downsized without requiring a large-capacity image memory. A conveying path conveys an original. Sensors are arranged on the conveying path, for detecting the conveyed original. CCD line sensors read the conveyed original. A CPU of the image reader decides the size of the conveyed original based on the results of detection by the sensors. An image memory stores image data output from the line sensors. The CPU transmits the decided original size and the stored image data to a controller. When the CPU cannot decide the original size at a predetermined timing, it transmits one of original size candidates to the controller, as a provisional original size. When the size of the original decided afterwards is different from the provisional original size, the CPU retransmits the decided size of the original.

Abstract: Provided is a document reading apparatus capable of suppressing a shock that may occur when a trailing edge of a tabbed sheet passes through a roller pair. In an image reading section, when a document to be read is the tabbed sheet, a timing to start separation of the roller pair in response to detection of a trailing edge of the document is delayed by a time period corresponding to a tab length with respect to the timing to start separation when a document other than the tabbed sheet is conveyed. Thus, it is possible to prevent the shock when the trailing edge of the tabbed sheet passes through the roller pair, and to thereby suppress image reading failure due to the shock.

Abstract: Provided is a document reading apparatus capable of suppressing a shock that may occur when a trailing edge of a tabbed sheet passes through a roller pair. In an image reading section, when a document to be read is the tabbed sheet, a timing to start separation of the roller pair in response to detection of a trailing edge of the document is delayed by a time period corresponding to a tab length with respect to the timing to start separation when a document other than the tabbed sheet is conveyed. Thus, it is possible to prevent the shock when the trailing edge of the tabbed sheet passes through the roller pair, and to thereby suppress image reading failure due to the shock.

Abstract: A sheet feeding device includes a separation roller, a first conveyance roller arranged on a downstream side of the separation roller and conveys the sheet separated by the separation roller, a second conveyance roller further conveys the sheet conveyed by the first conveyance roller, wherein the separation roller and the first conveyance roller are driven exclusively of each other by a first motor, and a control unit controls such that, when a trailing edge of a sheet passes through the separation roller while the sheet is being conveyed by the first conveyance roller and the second conveyance roller, the first motor makes a conveyance speed of the first conveyance roller higher than the conveyance speed thereof before the trailing edge of the sheet passes through the separation roller, and that, when the trailing edge of the sheet passes through the first conveyance roller, the first motor drives the separation roller.

Abstract: An original reader capable of being downsized without requiring a large-capacity image memory. A conveying path conveys an original. Sensors are arranged on the conveying path, for detecting the conveyed original. CCD line sensors read the conveyed original. A CPU of the image reader decides the size of the conveyed original based on the results of detection by the sensors. An image memory stores image data output from the line sensors. The CPU transmits the decided original size and the stored image data to a controller. When the CPU cannot decide the original size at a predetermined timing, it transmits one of original size candidates to the controller, as a provisional original size. When the size of the original decided afterwards is different from the provisional original size, the CPU retransmits the decided size of the original.

Abstract: An image forming apparatus which makes it possible to resolve correction error of potential unevenness caused by insufficient mounting accuracy of an image carrier, in a relatively short time period without performing a conventional operation for removing the image carrier. The image forming apparatus includes a photosensitive drum, an exposure unit, an electrical potential sensor, a shading data ROM, and a CPU. Electrical potential data items associated with respective positions on the surface of the photosensitive drum are stored in the shading data ROM. The CPU corrects an exposure amount onto the photosensitive drum by the exposure unit, based on the electrical potential data read from the ROM, and based on the result of correction, adjusts timing for reading out the data.

Abstract: An image forming apparatus which makes it possible to resolve correction error of potential unevenness caused by insufficient mounting accuracy of an image carrier, in a relatively short time period without performing a conventional operation for removing the image carrier. The image forming apparatus includes a photosensitive drum, an exposure unit, an electrical potential sensor, a shading data ROM, and a CPU. Electrical potential data items associated with respective positions on the surface of the photosensitive drum are stored in the shading data ROM. The CPU corrects an exposure amount onto the photosensitive drum by the exposure unit, based on the electrical potential data read from the ROM, and based on the result of correction, adjusts timing for reading out the data.