Patent ID: 7630657
Filing Date: 2009-12-08
Classification: G03G

Abstract:
1. An image forming apparatus, comprising: a plurality of image bearing members configured to bear respective images thereon; a transfer device configured to transfer the respective images formed on the plurality of image bearing members, including a transfer member in a form of a closed loop, and configured to receive the respective images on one of a surface of the transfer member and a recording medium carried by the transfer member; an image detecting unit configured to detect the respective images conveyed on the transfer member; a paper length detecting unit configured to detect a length of the recording medium in a sheet travel direction; a counting unit configured to count a number of recording media including the recording medium conveyed to the transfer device by changing a count up value each time a recording medium is conveyed to the transfer device according to a detection result obtained by the paper length detecting unit, and to add a value to the count value of the number of recording media conveyed to the transfer device according to an internal temperature of the image forming apparatus; and a control unit configured to control an image forming timing with respect to the plurality of image bearing members based on a detection timing of one of the respective images detected by the image detecting unit and to perform a positional deviation adjustment each time a count value of the number of recording media obtained by the counting unit increases by a predetermined amount, so as to reduce an amount of a positional deviation of the image caused when the image is superimposed on the transfer member or on the recording medium.