IP Library › Granted Patent US 5,333,638
Granted Patent Utility
US 5,333,638 · App. 08/006,934

Automatic recirculation valve

Inventor: Horace J. Maxwell
Patented Case View Patent ↗
Granted: Aug 2, 1994 Filed: Jan 21, 1993
Inventor
Horace J. Maxwell
Assignee (at issue)
Keystone International

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Quick Facts
Patent No.
US 5,333,638
App. No.
08/006,934
Filed
1993-01-21
Granted
1994-08-02
Kind
A