Granted Patent
Utility
US 4,842,491 · App. 07/155,431
Apparatus and method of determining compressor structural resonant frequency
Inventor:
Chih-Ming Lin
Patented Case
View Patent ↗
Granted: Jun 27, 1989
Filed: Feb 12, 1988
Inventor
Chih-Ming Lin
Assignee (at issue)
American Standard Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.