| 摘要 |
PROBLEM TO BE SOLVED: To control the moving speed of a belt with more accuracy by eliminating an error resulting from the thickness unevenness of the belt and eccentricity of a roller shaft which are superimposed on the measured moving speed of the belt. SOLUTION: This printer includes a laser Doppler speedometer 311 detecting the moving speed of a surface directly under ejection of an ink head and the angular speed of rotation of a driven roller as the belt surface moving speed in a conveyor belt 160, and a driven side encoder 310. The printer further includes a speed ratio computing part 401 extracting speed ratio data (profile data) having a frequency corresponding to a speed ratio, as belt profile data and roller profile data from the temporal variation of the measured speed ratio; a storage part 332 storing the profile data; and a correction control part 331 controlling each image forming timing by a head unit 110 to reduce a positional deviation between a plurality of images on the conveyor belt 160 based on each profile data. COPYRIGHT: (C)2010,JPO&INPIT |
