IP Library › Granted Patent US 4,310,257
Granted Patent Utility
US 4,310,257 · App. 06/103,818

Typewriter cartridge lock-down

Inventors: Thomas R. Field, Mary L. VanArsdall
Patented Case View Patent ↗
Granted: Jan 12, 1982 Filed: Dec 14, 1979
Inventors
Thomas R. Field
Mary L. VanArsdall
Assignee (at issue)
International Business Machines Corporation

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Quick Facts
Patent No.
US 4,310,257
App. No.
06/103,818
Filed
1979-12-14
Granted
1982-01-12
Kind
A