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:
Oct. 25, 1994
Filed:
Jun. 11, 1992
Tomoaki Nakano, Yokohama, JP;
Hiromichi Komai, Yokohama, JP;
Toshitaka Hirata, Tokyo, JP;
Toshio Inada, Sagamihara, JP;
Masami Kadonaga, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An ink jet printing head driving method includes steps of: applying a voltage falling edge of a first pulse signal to cause a piezoelectric element to contract so that a capacity of a liquid passage is increased so as to supply ink to the liquid passage; applying a voltage rising edge of the first pulse signal to cause the piezoelectric element to expand so that the capacity of the liquid passage is decreased, for discharging an ink droplet through a discharge port, the first pulse signal having a first pulse width and a first peak voltage amplitude; and applying a voltage rising edge of a second pulse signal to the piezoelectric element after a predetermined delay time has elapsed since application of the first pulse signal for discharging the ink droplet, a pulse width of the second pulse signal being smaller than the first pulse width, and a peak voltage amplitude of the second pulse signal being equal to the first peak voltage amplitude.