Patent ID: 7673956
Filing Date: 2010-03-09
Classification: B41J

Abstract:
1. A print head inspection method according to which inspects a print head in which a nozzle-forming member forming a plurality of nozzles is provided by utilizing a print head inspection apparatus comprising a print recording liquid-receiving area that can receive print recording liquid ejected from the nozzles, the print head inspection method including steps of: (a) applying a predetermined voltage so as to generate a predetermined potential difference between the print recording liquid in the print head and the print recording liquid-receiving area; (b) following step (a) detecting the potential difference between the print recording liquid in the print head and the print recording liquid-receiving area; and (c) when the potential difference detected in step (b) is within a predetermined permissible range, applying pressure sequentially to the print recording liquid in every nozzle, detected an electrical change in the print recording liquid in the print head, or in the print recording liquid-receiving area, and on the basis of the electrical change detected, performing a nozzle inspection so as to establish whether or not print recording liquid has been ejected from individual nozzle, wherein the print head inspection apparatus comprises a distance-varying module that is capable of varying a relative distance between the print recording liquid-receiving area and the nozzle-forming member, and wherein, when the potential difference detected in step (b) is less than the permissible range, step (c) is a step of performing the nozzle inspection after the distance-varying module has been controlled so as to increase the relative distance.