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, 1989
Filed:
Jan. 25, 1989
Kenneth E Trueba, Corvallis, OR (US);
William R Knight, Corvallis, OR (US);
Niels J Nielsen, Corvallis, OR (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
The use of lumped resistive elements (28) in an ink feed channel (10) between an ink-propelling element, such as a resistor, (12) and an ink supply plenum (14) provides a means of achieving resistive decoupling and meniscus resonance control with a minimum of deleterious side effects and design compromises typical of prior art solutions. A secondary constriction (30) in the ink feed channel is defined by a width W.sub.2 sufficient to provide physical support for the resistive elements while avoiding resistance to ink refill. The printhead further comprises lead-in lobes (38) for assisting in purging any bubbles in the ink. The lobes are disposed between the projections and the plenum chamber and separate one pair of projections from a neighboring pair.