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:
Sep. 11, 1984
Filed:
Aug. 25, 1981
Seiji Hanaoka, Shiojiri, JP;
Epson Corporation, Nagana, JP;
Kabushiki Kaisha Suwa Seikosha, Tokyo, JP;
Abstract
In the demand-type ink jet printer head driving method and apparatus a predetermined voltage is applied to an electromechanical conversion device in a preliminary step to displace the wall of an ink pressure chamber inwardly. This decreases the volume of the pressure chamber without ejecting ink from the nozzle. The applied voltage is removed to restore the wall of the pressure chamber by means of the elastic energy stored in the wall and in the electro-mechanical conversion means thereby drawing ink into the pressure chamber from an ink reservoir container. Voltage is applied a second time to the electro-mechanical conversion device in synchronism with a damped oscillation system comprised of the pressure chamber wall, the electro-mechanical conversion means, and ink. The second application of voltage in synchronism with the damped oscillation displaces the electro-mechanical conversion means inwardly so that an ink droplet is ejected from the nozzle.