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. 06, 1992
Filed:
Jan. 03, 1991
Applicant:
Inventors:
John B Dunn, Corvallis, OR (US);
Bruce Cowger, Corvallis, OR (US);
Assignee:
Hewlett-Packard Company, Palo Alto, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B41J / ;
U.S. Cl.
CPC ...
3461 / ;
Abstract
A flexible reservoir bladder is connected to the base of a pen body to define a reservoir volume that permits nearly all of the ink contained therein to be delivered from the pen by a print head. The back pressure developed within the reservoir volume is regulated by the resilient properties of the bladder and an orifice that permits controlled entry of air into the volume as the ink is depleted. The system is able to withstand severe environmental effects, such as a drop in ambient air pressure, while preventing pen leakage.