The EOS mechanical calculator
Channel: Jaap Scherphuis
Date: 08/05/2021

The EOS calculator is identical to the Hannovera model CK, but was made for the Swiss market. It uses an oscillating toothed segment mechanism which was easier to manufacture and did not infringe on Brunsviga's patents, unlike Hannovera's previous models which were pinwheel machines. The mechanism is similar to that of the Demos, but better because it can do subtraction by turning the crank in reverse.

I show the mechanism of the EOS in another video: https://youtu.be/pWOyLou-uys

For more information on this and other machines in my collection, please visit my website:
https://www.jaapsch.net/mechcalc/

0:00 Introduction, History
1:28 Addition
2:58 Subtraction
3:21 Counter
3:50 Clearing
4:20 Shifting the carriage
5:39 Serial number
6:52 Outro