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:
Dec. 27, 1988
Filed:
Dec. 03, 1987
Applicant:
Inventors:
Bruce Cowger, Corvallis, OR (US);
Robert Beeson, Corvallis, OR (US);
Assignee:
Hewlett-Packard Company, Palo Alto, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01D / ;
U.S. Cl.
CPC ...
3461 / ; 222187 ; 222189 ;
Abstract
An ink jet pen (or other similar fluid delivery system) wherein primary and secondary ink reservoirs and an ink jet printhead are all interconnected by way of a porous ink-transfer member. The ink will pass directly from the primary ink reservoir to the printhead under a normal or predetermined range of temperatures and pressures. However, for temperatures and pressures outside this range, the secondary reservoir will be brought into operation to give or receive ink to or from the porous ink transfer member and thereby serve to maintain a substantially constant backpressure at the printhead.