IP Library › Granted Patent US 5,931,821
Granted Patent Utility
US 5,931,821 · App. 08/810,056

Chest drainage unit with controlled automatic excess negativity relief feature

Inventors: Eugene E. Weilbacher, David Rork Swisher
Patented Case View Patent ↗
Granted: Aug 3, 1999 Filed: Mar 4, 1997
Inventors
Eugene E. Weilbacher
David Rork Swisher
Assignee (at issue)
Tyco Group S.a.r.l.

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Quick Facts
Patent No.
US 5,931,821
App. No.
08/810,056
Filed
1997-03-04
Granted
1999-08-03
Kind
A