Method and a device for detecting clogged nozzles

摘要

A device and a method for automatically detecting and clearing clogged nozzles. To detect clogged nozzles a print head controller causes a print head to print on a sheet of paper by sending a number of electric signals that cause the print head to expel ink through nozzles. The print head controller sends an electric-signal causing a print head to print. A scanner scans the area on the paper where the print head was supposed to have ejected ink. Then, an image processor converts the read data into binary data. The binary data is then analyzed by a detection processor that determines if there is any indication of missing ink drops. If missing ink drops are detected, a nozzle cleaning processor sends signals to the print head to cause the clogged nozzles to purge and expel impurities so that optimum printing quality is restored.