IP Library › Granted Patent US 4,491,778
Granted Patent Utility
US 4,491,778 · App. 06/604,445

Motor variable frequency drive

Inventors: Dick L. Knox, John M. Leuthen, Kevin W. Lockyear
Patented Case View Patent ↗
Granted: Jan 1, 1985 Filed: Apr 30, 1984
Inventors
Dick L. Knox
John M. Leuthen
Kevin W. Lockyear
Assignee (at issue)
Hughes Tool Company LLC

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Quick Facts
Patent No.
US 4,491,778
App. No.
06/604,445
Filed
1984-04-30
Granted
1985-01-01
Kind
A