Jaap's Mechanical Calculators Page

Stima

Stima


Description
History
Advertisements and Articles
Patents
Links


The Stima is a 9-digit adding machine. It resembles a slide adder such as the Pocket Adding Machine, but it has an automatic carry mechanism so the way it is used is more like the SuN chain adder. On the front there are nine vertical slots, with a slider inside. Beside each slot there are the digits from 9 (top) to 1 (bottom). The sliders have holes next to the digits, and to enter a digit in any column you put the stylus in the relevant hole, and slide it down to the bottom. Directly below the sliders is a register, consisting of holes through which the entered digits are visible.

The results register is at the bottom of the face of the machine. Any number you enter is automatically added to this register. If you press the red button to the right of the register you clear the input, so the sliders spring up to their starting positions again. You can then input the next number to add to the register. To clear the register, pull out the white button on the right hand side of the machine.

The green button at the top can be pushed inwards for multiplication mode, in which the sliders automatically spring back. This way you can enter a digit several times in quick succession, allowing for simple multiplications.

Stima CMIII
Stima CMIII
Stima CMIII
Stima CMIII
Stima CMIII
Stima CMIII


This is the desktop model, which has a Bakelite case. This is really just an outer shell that holds the flat metal calculator at an angle for ease of use on a desk. When the screws inside the rubber feet are removed, the flat base comes off showing the empty interior. The serial number 19458 is found on the inner metal case and on the Bakelite base.

Stima CMIII
Stima CMIII



History

The Stima was invented and patented by Albert Steinmann in 1930, and he started to produce it around the same time. He was based in La Chaux-De-Fonds, which is in Switzerland very close to the border of France. The first models were metal and rectangular in shape, and were available with 7, 8, or 9 digits. Note that these variants had the same dimension, but those with fewer digits simply did not use the full width of the front face. The internal mechanism of the Stima uses very small precision-engineered parts, like the watches the Swiss were famous for.

At first the Stima did not have a multiplication lever, but this became standard from about 1933 or so. The lens over the main register was an optional extra. Later, some versions also had a subtraction button. While this button was pressed, the main register would not be affected when the sliders moved down, and the subtraction would take place when the sliders were reset.

The variants are generally designated by the following letters in order:
C: Destop model, has Bakelite case.
M: With multiplication lever or button.
S: Subtraction button.
I to III: 7 to 9 digits. Apparently there was also a Junior version with 5 digits.
My Stima is therefore a CM-III.

Production continued at least until 1947, but I do not know when it ended.


Advertisements and Articles

Here are a few Dutch advertisements of the Stima that I found in online archives.

1934-03-24 Limburgsch dagblad
1937-09-20 Nieuwsblad van het Noorden
1947-01-24 De West (Suriname)



Patents

Albert Steinmann patented the Stima in 1930.

PatentFiling datePriority dateNameDescription
CH 146,89927-03-193016-07-1931Albert SteinmannStima
See also DE 572,387 C, US 1,875,519.
CH 146,90024-04-193016-07-1931Albert SteinmannStima clearing mechanism
See also DE 541,508 C

Links

Rechnerlexikon has an informative Stima page.
Rechenmaschinen-Illustrated has photos of a Stima MS-III, including photos of a manual.
The Computer History Musem owns an early Stima I.
Mechanicalculator.com has a Stima CM-III.


© Copyright 2018 Jaap Scherphuis, .