Patent ID: 6137981
Filing Date: 2000-10-24
Classification: G03G

Abstract:
An image-forming apparatus for forming multiple toner images in register with each other on a substrate in sheet form, said apparatus comprising:an endless belt;an imaging station at which a plurality of electrostatic images are sequentially formed on said belt;plurality of developing stations at which said electrostatic images are developed into toner images on said belt;a plurality of transfer stations at which said toner images are transferred to a substrate;a belt drive device for driving said endless belt along a belt path through said imaging station, said developing stations and said transfer stations; anda control device for controlling said belt drive device to run at a constant speed, characterized by:a preformed timing mark carried on said belt; anda sensor for sensing passage of said timing mark past a sensing position, andwherein said control device is adapted to control the speed of said belt in response to sensing of said timing mark such that the time interval between two successive sensings of said timing mark is kept constant.