IP Library Granted Patent US 4,418,921
Granted Patent Utility
US 4,418,921 · App. 06/261,870

Mechanical seal

Inventors: Winfred J. Wiese, Joseph A. Marsi
Patented Case View Patent ↗
Granted: Dec 6, 1983 Filed: May 8, 1981
Inventors
Winfred J. Wiese
Joseph A. Marsi
Assignee (at issue)
BorgWarner Inc.

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Quick Facts
Patent No.
US 4,418,921
App. No.
06/261,870
Filed
1981-05-08
Granted
1983-12-06
Kind
A