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:
Apr. 02, 1985
Filed:
Nov. 23, 1982
Applicant:
Inventors:
Robert N Low, Corvallis, OR (US);
Frank L Cloutier, Corvallis, OR (US);
Gary Siewell, Albany, OR (US);
Assignee:
Hewlett-Packard Company, Palo Alto, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01D / ;
U.S. Cl.
CPC ...
3461 / ; 400126 ;
Abstract
An ink reservoir which incorporates a negative back pressure source coupled to a membrane wall of the reservoir to prevent ink leakage from a reservoir orifice is disclosed. The back pressure is created by either a linear or nonlinear spring which can be either independent of, or integral with, the membrane. The result is freedom from ink leakage and improved quality printing when the reservoir is used in conjunction with an ink pen such as used in ink jet printing.