[Main Page]

Rechnerlexikon

Die große Enzyklopädie des mechanischen Rechnens

3.95.131.97 | 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:US3147556


Patent:US 3147556
Title:Calculating Device
Date:08.09.1964
Place:
Country:USA
Person:Prusmack, Murray (P)
Company:
Internal Links:Rechenschieber, ABA-Ten Rule, Lehrmittel
Keywords:slide rule
Link to the patent office:
(without guarantee)
 US3147556 (espacenet),  US3147556 (uspto)


"This invention relates to teaching aids and more particularly to a new and useful calculating device for introducing children of the kindergarten and lower grammar school grades to basic concepts in various branches of mathematics.

It is a primary object of present coordinates the sense of touch with the sense of sight to physically present and demonstrate a variety of basic number groupings in the arts of addition, subtraction, multiplication, and division and the number facts of these groupings in a manner which assists the young student in correlating abstract numerical symbols with corresponding physical entities." Aus der Patentschrift.

aus der Patentschrift