Patent ID: 8540334

Claim:
An image forming apparatus comprising: a paper feed section configured to set a plurality of sheets; an image forming section configured to form an image on the sheet; a mechanism configured to transport the sheet in a transport path defined from the paper feed section to a sheet paper ejection port through the image forming section; a sheet sensor configured to detect a leading edge and a trailing edge of the sheet in the transport path; a sensor power source configured to supply electric power to the sheet sensor; a detecting section configured to specify the position of the sheet transported by the mechanism based on the position of the sheet sensor in the transport path and a detection output from the sheet sensor; and a driving control section configured to generate a timing signal indicating a first detection period when a leading edge of the sheet is detected and a timing signal indicting a second detection period when a trailing edge of the sheet is detected, by the sheet position, turn on the sensor power source in the first detection period and the second detection period, and turn off the sensor power source in a period different from the respective detection periods.