IP Library › Granted Patent US 4,989,774
Granted Patent Utility
US 4,989,774 · App. 07/394,984

Structural box beams

Inventors: David Stephen, Martin H. Mansbridge, David J. Irwin
Patented Case View Patent ↗
Granted: Feb 5, 1991 Filed: Aug 17, 1989
Inventors
David Stephen
Martin H. Mansbridge
David J. Irwin
Assignee (at issue)
British Aerospace Public Limited Co.

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Quick Facts
Patent No.
US 4,989,774
App. No.
07/394,984
Filed
1989-08-17
Granted
1991-02-05
Kind
A