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:
Nov. 21, 1978
Filed:
Aug. 29, 1977
Richard G Stevenson, Jr, Palo Alto, CA (US);
Silonics, Inc., Sunnyvale, CA (US);
Abstract
An electronic circuit for driving an ink jet print head of the type wherein a droplet of ink is ejected from an ink chamber through an orifice upon demand by pulsing a piezoelectric element in a manner to suddenly reduce the volume of the chamber. Switching circuits responsive to a low level control signal cooperatively energize the piezoelectric element for the duration of a control pulse and discharge the inherent capacitance of the crystal at the end of the control pulse. A storage capacitor is connected in a way to reduce the current drain on the power supply. Critical semi-conductor switching elements are provided with variable biases to maximize their switching speed.