Granted Patent
Utility
US 4,642,852 · App. 06/744,271
Dust extractor for drawframe
Inventors:
Nicholas J. Turner, Geoffrey A. Ogden, Richard S. Bridge
Patented Case
View Patent ↗
Granted: Feb 17, 1987
Filed: Jun 13, 1985
Inventors
Nicholas J. Turner
Geoffrey A. Ogden
Richard S. Bridge
Assignee (at issue)
NATIONAL RESEARCH DEVELOPMENT CORPORATION
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.