IP Library › Granted Patent US 4,932,401
Granted Patent Utility
US 4,932,401 · App. 07/176,862

Two-gas variable ratio, variable dose, metering system and method of use

Inventor: Warren E. Perkins
Patented Case View Patent ↗
Granted: Jun 12, 1990 Filed: Apr 1, 1988
Inventor
Warren E. Perkins

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Quick Facts
Patent No.
US 4,932,401
App. No.
07/176,862
Filed
1988-04-01
Granted
1990-06-12
Kind
A