IP Library › Granted Patent US 4,845,820
Granted Patent Utility
US 4,845,820 · App. 07/053,316

Process for making cassette spring

Inventor: William M. Carroll
Patented Case View Patent ↗
Granted: Jul 11, 1989 Filed: May 22, 1987
Inventor
William M. Carroll
Assignee (at issue)
Koller Manufacturing Corporation

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Quick Facts
Patent No.
US 4,845,820
App. No.
07/053,316
Filed
1987-05-22
Granted
1989-07-11
Kind
A