Patent ID: 6089693
Filing Date: 2000-07-18
Classification: B41J

Abstract:
A liquid ink printer for depositing ink drops to form an image responsive to image data on a recording medium moving along a recording medium path, comprising:a positionable pagewidth printbar, including an array of ink ejecting nozzles, aligned with and movable in a direction substantially perpendicular to the recording medium path, the printbar ejecting the ink drops on the recording medium during movement of the recording medium along the recording medium path and past said printhead, while the printbar is stationary;a nozzle identification circuit, coupled to said printbar, to generate a detection signal identifying a non-functioning nozzle of said array of ink ejecting nozzles;a positioning device, coupled to said pagewidth printbar, to position said printbar at a selected one of a plurality of discrete locations along said direction which is substantially perpendicular to the recording medium path; anda controller comprising a nozzle control circuit to receive said detection signal and to generate in response thereto a control signal to identify image data corresponding to said identified non-functioning nozzle, said controller coupled to said positioning device and to said nozzle identification circuit to cause said positioning device to change position of said printbar to a different one of said plurality of discrete locations as a function of said detection signal, after said recording medium has completed movement past said printbar, whereupon said controller causes said recording medium to move along said recording medium path and past said printbar again, so that the printbar may deposit ink drops from a selected functioning nozzle, on the recording medium corresponding to the identified image data not printed by said identified non-functioning nozzle.