Patent ID: 7410236
Filing Date: 2008-08-12
Classification: B41J

Abstract:
1. A method of testing an inkjet head, the inkjet head including a plurality of nozzles, a plurality of pressure chambers communicating with the nozzles, respectively, a cavity unit having an ink flow passage along which ink from an ink supply source reaches to the nozzles via the pressure chambers, and an actuator that is displaced by application of a driving waveform to selectively apply ejection pressure to each pressure chamber, the inkjet head ejecting ink drops from the nozzles to perform recording on a recording medium, the method comprising: sorting inkjet heads into a plurality of groups on the basis of known information about ejection characteristics of the inkjet heads, and preparing a plurality of kinds of basic driving waveforms that correspond to respective groups; storing the plurality of kinds of basic driving waveforms in a storing section as basic driving waveform data in association with identification information of the basic driving waveforms; storing a plurality of kinds of modification data to partially modify the basic driving waveform data in association with identification information; determining, with respect to an inkjet head to be tested, basic driving waveform data to be applied to the inkjet head on the basis of the group to which the inkjet head belongs, and creating individual waveform information including the identification information of the determined basic driving waveform data and information showing that the basic driving waveform data is not modified; creating the driving waveform with out modifying the basic driving waveform data on the basis of the created individual waveform information, and ejecting ink drops onto a recording medium on the basis of the created driving waveform; creating new individual waveform information when a recording state on the recording medium is bad by changing the individual waveform information so as to include the identification information of the determined basic driving waveform data and the identification information of the modification data to modify the basic driving waveform data; and modifying the basic driving waveform data according to the modification data to create a new driving waveform on the basis of the recreated driving waveform information when the recording state on the recording medium is bad, and ejecting the ink drops onto the recording medium on the basis of the new driving waveform, wherein the driving waveform to be applied to the actuator is created by repeating the modification of the individual waveform information until the recording state on the recording medium becomes good.