A method of performing error notification and error recovery functions in an image forming apparatus includes detecting by one or more sub-processors an error of a main processor for controlling the sub-processors; controlling an interface function of the image forming apparatus if the error is detected; outputting information about the detected error; and recovering the detected error by controlling an operation of the main processor.

Provided is an image-forming device that can execute operations that do not use a document-reading unit even when abnormality in a light source is detected in the initial operation at startup. The image-forming device includes a document-reading unit, and together with being able to execute image-forming operations that use the document-reading unit, is able to execute image-forming operations that do not use the document-reading unit. The image-forming device includes a light-source-abnormality-detection unit that executes a light-source-abnormality-detection operation, and when an abnormality in the light source is detected by the light-source-abnormality-detection operation that is executed at startup, stores the startup signal level that is outputted in a light-source-abnormality-storage unit as light-source-abnormality information. The image-forming device performs normal startup in which all image-forming operations can be executed regardless of the detection results of the light-source-abnormality-detection operation.

A document conveyance apparatus includes a document conveyance section, a cover, an opening and closing detection sensor, a document detection sensor, and a control section. The control section detects opening and closing of the cover on the basis of an output value of the opening and closing detection sensor and detects whether or not there is a document in a predetermined detection position on the basis of the output value of the document detection sensor. If, when the output value of the document detection sensor has changed from a value indicating an opened state of the cover to a value indicating a closed state thereof, the output value of the document detection sensor is a value indicating that there is the document, the control section detects a half-closed state where the cover is not completely closed.

An image forming apparatus includes plural components that are used to perform an image forming operation, and a drive controller that controls a potential noise source component or a component group containing plural potential noise source components among the plural components to be sequentially driven in an operation state for specifying a noise occurrence place such that a component or a component group having a higher possibility to be a noise source is driven with higher priority or a component or a component group having a lower possibility to be the noise source with lower priority.

An image forming apparatus includes a conversion unit configured to convert image data based on a conversion condition, an image forming unit configured to form an image on a sheet based on the converted image data, a detection unit configured to detect a pattern image on a transfer member, a reading unit configured to read a test image formed on a sheet, a controller configured to perform calibration based on a reading result of the reading unit, and a reception unit. In a case where the calibration is performed, the controller determines an image forming condition based on a result of detection by the detection unit before the test image is formed. In a case where the reception unit receives the discontinuation instruction, the controller changes the image forming condition to an image forming condition before the pattern image is formed.

An image forming apparatus combines a plurality of sub-movies representing operation procedures to be performed to perform maintenance on the image forming apparatus and plays the combined sub-movies sequentially as one movie. In response to stopping the movie being played, the image forming apparatus displays a replay mark for use to issue a command to replay the movie from the beginning of a sub-movie corresponding to a position where the movie is stopped.

Methods and apparatus pertaining to scanning or copying documents are provided. Sheet media are individually transported away from an input location. Optical scanning of the sheet media is initiated in accordance with detecting the passage of leading edges of the sheet media. Electronic signals resulting from the scanning are automatically analyzed to detect trailing edges of overlapping sheet media. A user notification is issued if a multiple sheet pick event is detected. A user can resume scanning or copying of a multiple sheet document at the location where the multiple sheet pick occurred.

A sensor unit includes a sensor device, a holder that holds the sensor device and includes a surface maintained at a reference potential, and a case that houses the holder, in which the case includes a mounting surface in contact with a mounting object, and the mounting surface is provided with a communication portion that causes an inside and an outside of the case to communicate with each other, and the holder includes a protrusion that protrudes from the communication portion and comes in contact with the mounting object.

An inspection apparatus is provided, which is operable to inspect a cut sheet that is supplied to a post-processing apparatus that post-processes sheets in units of hooks and on which an image has been formed by an image forming apparatus. The inspection apparatus inspects an image formed on a sheet for each sheet; manages results of sheet inspection by the inspection unit for respective books including a plurality of sheets; and notifies, the post-processing apparatus of a result of inspecting a book including the sheet that is based on the managed sheet inspection results.

An image forming apparatus operable by an operation device includes a storage that stores a plurality of operations, a detector that detects an operation, and a controller. The controller registers a terminal as the operation device if an operation detected by the detector conforms with an operation stored in the storage.