IP Library › Granted Patent US 5,339,857
Granted Patent Utility
US 5,339,857 · App. 07/972,616

Media assisted valves

Inventors: David J. Scallan, George W. Parker
Patented Case View Patent ↗
Granted: Aug 23, 1994 Filed: Nov 6, 1992
Inventors
David J. Scallan
George W. Parker
Assignee (at issue)
Dresser Industries, Inc.

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Quick Facts
Patent No.
US 5,339,857
App. No.
07/972,616
Filed
1992-11-06
Granted
1994-08-23
Kind
A