IP Library › Granted Patent US 4,640,492
Granted Patent Utility
US 4,640,492 · App. 06/694,097

Involute valve closure

Inventor: William L. Carlson
Patented Case View Patent ↗
Granted: Feb 3, 1987 Filed: Jan 23, 1985
Inventor
William L. Carlson
Assignee (at issue)
Federal Signal Corporation

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Quick Facts
Patent No.
US 4,640,492
App. No.
06/694,097
Filed
1985-01-23
Granted
1987-02-03
Kind
A