Ink jet printing apparatus, ink jet printing method, and preliminary discharge control method - Patents

Patent Agent: Fitzpatrick Cella Harper & Scinto - New York, NY, US
Patent Inventors: Tetsuya Edamura, Kiichiro Takahashi, Minoru Teshigawara, Akiko Maru, Yoshiaki Murayama
Applicaton #: 20070008367
Class: 347019000 (USPTO)
01/11/07
On performing a predetermined printing operation, whether or not, among a plurality of printing elements, only a part of the printing elements are applied is detected. If it is judged that only the part of the printing elements are used, a judgment is made whether or not the preliminary discharge operation is performed based on the number of discharges for the part of the printing elements, and if it is not judged that only the part of the printing elements are used, a judgment is made whether or not the preliminary discharge operation is performed based on the number of discharges for all of the printing elements of the printing head. This eliminates an unnecessary preliminary discharge for non-printing elements even in a printing operation mode in which only a part of the printing elements are applied.
SUMMARY OF THE INVENTION
[0014] The present invention has been made in view of the foregoing problem and therefore has an object to provide an ink jet printing apparatus and a preliminary discharge control method which are capable of performing a more efficient preliminary discharge operation in terms of ink consumption and throughput even when the number of nozzles to be used is limited for image formation as in the "margin-less printing".
[0015] The first aspect of the present invention is an ink jet printing apparatus for printing an-image on a printing medium using a printing head having a plurality of printing elements to discharge ink, comprising: means for counting the number of discharges by the printing elements of the printing head; means for judging whether or not a preliminary discharge operation of the printing head is necessary, based on the number of discharges obtained by the counting means; and means for performing the preliminary discharge by the printing elements of the printing head in accordance with a result of the judgment by the judging means, wherein when a printing operation is performed using only a part of the printing elements among the plurality of the printing elements of the printing head, the judging means judges whether or not the preliminary discharge operation is necessary based on the number of discharges counted for the part of the printing elements.
A subscription is required to view the entire article.