IP Library › Granted Patent US 4,920,237
Granted Patent Utility
US 4,920,237 · App. 07/305,585

Membrane keyboards

Inventors: Richard A. Eardley, Brian J. Keenan, Ian A. Lawson, John J. McAllister
Patented Case View Patent ↗
Granted: Apr 24, 1990 Filed: Feb 2, 1989
Inventors
Richard A. Eardley
Brian J. Keenan
Ian A. Lawson
John J. McAllister
Assignee (at issue)
International Business Machines Corporation

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Quick Facts
Patent No.
US 4,920,237
App. No.
07/305,585
Filed
1989-02-02
Granted
1990-04-24
Kind
A