IP Library › Granted Patent US 4,822,001
Granted Patent Utility
US 4,822,001 · App. 07/143,198

Positive fluid seal butterfly valve

Inventor: David E. Sisk
Patented Case View Patent ↗
Granted: Apr 18, 1989 Filed: Jan 13, 1988
Inventor
David E. Sisk

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Quick Facts
Patent No.
US 4,822,001
App. No.
07/143,198
Filed
1988-01-13
Granted
1989-04-18
Kind
A