IP Library › Granted Patent US 4,425,640
Granted Patent Utility
US 4,425,640 · App. 06/255,487

Telecommunications switching network using digital switching modules

Inventors: Alexander S. Philip, Thomas S. Maddern
Patented Case View Patent ↗
Granted: Jan 10, 1984 Filed: Apr 20, 1981
Inventors
Alexander S. Philip
Thomas S. Maddern
Assignee (at issue)
The Plessey Company PLC

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Quick Facts
Patent No.
US 4,425,640
App. No.
06/255,487
Filed
1981-04-20
Granted
1984-01-10
Kind
A