[Main Page]

Rechnerlexikon

Die große Enzyklopädie des mechanischen Rechnens

18.232.51.247 | Log in | Help

  DE  EN  FR  IT 
Main Page
All pages
Recent changes

Printable version
Discuss article

article
image
patent



Special pages
Pfeil.gif Patents  Pfeil.gif USA  

Patent:US3731401


Patent:US 3731401
Title:Abacus Instruction Device
Date:08.05.1973
Place:
Country:USA
Person:Tsuneji Kojima
Company:
Internal Links:Kugelrechner , Lehrmittel
Keywords:
Link to the patent office:
(without guarantee)
 US3731401 (espacenet),  US3731401 (uspto)


Enlarge

Aus der Patentschrift US3731401