IP Library › Granted Patent US 4,638,124
Granted Patent Utility
US 4,638,124 · App. 06/653,742

Key telephone system with distributed control

Inventors: Franklin Hargrave, Francisco A. Middleton
Patented Case View Patent ↗
Granted: Jan 20, 1987 Filed: Sep 21, 1984
Inventors
Franklin Hargrave
Francisco A. Middleton
Assignee (at issue)
ITT Corporation

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Quick Facts
Patent No.
US 4,638,124
App. No.
06/653,742
Filed
1984-09-21
Granted
1987-01-20
Kind
A