IP Library › Granted Patent US 4,677,447
Granted Patent Utility
US 4,677,447 · App. 06/842,594

Ink jet printhead having a preloaded check valve

Inventor: Niels J. Nielsen
Patented Case View Patent ↗
Granted: Jun 30, 1987 Filed: Mar 20, 1986
Inventor
Niels J. Nielsen
Assignee (at issue)
Hewlett-Packard Company, L.P.

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Quick Facts
Patent No.
US 4,677,447
App. No.
06/842,594
Filed
1986-03-20
Granted
1987-06-30
Kind
A