The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 30, 2002
Filed:
Aug. 27, 1999
Yoshitaka Akiyama, Hitachinaka, JP;
Takuji Torii, Hitachinaka, JP;
Nobuhiro Noto, Hitachinaka, JP;
Kazuaki Akimoto, Hitachinaka, JP;
Kazuo Shimizu, Hitachinaka, JP;
Shigenori Suematsu, Hitachinaka, JP;
Kenichi Kugai, Hitachinaka, JP;
Hitachi Koki Co., Ltd., Tokyo, JP;
Abstract
To increase the size of dot printed on a print medium with an on-demand multi-nozzle ink jet head, at least two unit pulses are applied in succession to a piezoelectric element which varies the volume of an ink chamber. The unit pulse has a pulse width substantially equal to a period of Helmholtz natural oscillation determined based on dimensions, materials, and physical properties of an ink channel and the piezoelectric element and other components relating to oscillation. An off duration between adjacent unit pulses applied in succession to the piezoelectric element is preferably set one fifth to one fourth of the unit pulse width.