Granted Patent
Utility
US 4,519,748 · App. 06/659,039
Micro-processor control of compression ratio at full load in a helical screw rotary compressor responsive to compressor drive motor current
Inventors:
David A. Murphy, Peter C. Spellar
Patented Case
View Patent ↗
Granted: May 28, 1985
Filed: Oct 10, 1984
Inventors
David A. Murphy
Peter C. Spellar
Assignee (at issue)
Frick Company
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.