Granted Patent
Utility
US 4,258,696 · App. 05/893,259
Passive thermal energy phase change storage apparatus
Inventor:
Raj Gopal
Patented Case
View Patent ↗
Granted: Mar 31, 1981
Filed: Apr 5, 1978
Inventor
Raj Gopal
Assignee (at issue)
Johnson Controls, 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.