CHARGING CONTROL-TYPE MULTI-NOZZLE INK JET RECORDER

摘要

PURPOSE:To erase white and black stripes and improve image quality through improvement of printing dot position control by pre-correcting a charging voltage with a bias value corresponding to the jet direction of a nozzle. CONSTITUTION:Uniform ink droplets are injected through a multihead 1 and charged by a charging electrode 2. At that time, a bias voltage is provided at each nozzle for adjustment of a jet direction of deflected ink droplets. The bias voltage is obtained as a charging voltage when detected by a detection circuit 22 after ink droplets are allowed to contact wire 11 set in parallel with a nozzle array while they are charged and deflected. Then a charging voltage is applied to the droplets in a phase where charging is allowed normally. A jet direction adjustment voltage (bias control circuit 16) and a distortion correction voltage which corrects charging distortion with printing sequence and delay in the ink droplet supply due to air resistance are added and applied to the charging electrode as a charging voltage. Thus the precision tolerance of nozzle fabrication becomes less severe and cost or reliability is improved.