IP Library › Granted Patent US 4,721,162
Granted Patent Utility
US 4,721,162 · App. 06/645,574

Fluid level controlled safety valve

Inventors: Ronald E. Pringle, Paul Black
Patented Case View Patent ↗
Granted: Jan 26, 1988 Filed: Aug 29, 1984
Inventors
Ronald E. Pringle
Paul Black
Assignee (at issue)
Camco Inc.

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Quick Facts
Patent No.
US 4,721,162
App. No.
06/645,574
Filed
1984-08-29
Granted
1988-01-26
Kind
A