Direct adding page 1 ( Comptometer mechanism) (under construction )

The comptometer is a special rocking segment application. It is a direct adding principle without activation by a lever of handle, you me call it a key driven mechanism. Each key press results directly in adding the number to the result and simultaneously the ten carry is executed. The first generations using 10 tooth's gears and numbered wheels, 0 to 9, on the side, one for every digit. These are alongside of each other and via a window they give shape to the result display.
The basic function, adding numbers, is started with a key press. This will turn the toothed segment. This will turn the gear with the numbers on the side and results in adding the number of the pressed key.
Later generations had a more complex mechanism, this to minimize the faults pressed or half pressed key's.
An other thing to point out is the tens cary mechanism. meaning the nine to ten transition. In words: The current gear goes to zero and the next digit-gear should add with one.