Electric control system for tabulating cards, documents, and the like
United States Patent 2224646

Inventors:
Friedman, William F.
Whitman, Vernon E.
Publication Date:
12/10/1940
View Patent Images:
Download PDF 2224646 pdf       PDF help
Export Citation:
Click for automatic bibliography generation
Assignee:
Friedman, William F.
Whitman, Vernon E.
Primary Class:
209/583
Other Classes:
209/657, 235/462.250, 250/555, 235/492, 340/5.100, 235/454, 235/494, 234/75