Patent ID: 7149449
Filing Date: 2006-12-12
Classification: G03G

Abstract:
1. A method of determining a relative speed between two separately driven members in an image forming apparatus, comprising the steps of: transporting a print medium using a print media transport assembly including a first nip, said print media transport assembly operable at a first transport speed; driving a rotatable member associated with a second nip at a second transport speed which is independent from said first transport speed; printing a first image on the print medium when the print medium is in at least one of said first nip and said second nip; printing a second image on the print medium when the print medium is in each of said first nip and said second nip, said second image overlapping said first image; detecting a moiré pattern caused by said first image and said second image; and determining a speed relationship between said first transport speed and said second transport speed, dependent upon said detected moiré pattern.