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Original-Odhner

Original-Odhner, model 24

The Original-Odhner 24 is a mechanical calculator with a pinwheel mechanism. It has 10 input levers for entering a 10-digit input. It has a carriage on which there is a main register with a large capacity of 20 digits, and a counter register with 11 digits. The counter has a carry mechanism. The input can be cleared by pushing a botton on the right which closes the input lever slots, after which you can turn the crank clockwise as far as it will go which causes the input pins to be pushed up, and then returning the crank to its resting position.

The choice of whether to increment or decrement the counter is selected automatically. After the counter is cleared, the first operation of the crank will increment the counter regardless of whether it is a subtraction or an addition, and this counter direction is then locked in for subsequent operations. The machine also has a back transfer mechanism, meaning that you can copy the value in the main register back into the input. If the input is clear, you can press the back transfer button on the right hand side of the carriage, and then clearing the main register performs the transfer.

This model does not have an input display register, but the model 25 does and is otherwise identical to this model 24.

The serial number is 24-244756, which dates the machine to about 1947.

Videos

The first video shows how to use the machine, while the second describes the mechanism.

History

Willgodt Theophil Odhner created his first working prototype pinwheel calculator in 1875. More machines were hand-built over the next few years, but mass production only started in 1890 from his workshop in Saint Petersburg. As production expanded, he licensed Grimme Natalis & Co in Germany to produce them as well, and they sold them under the brand name Brunsviga from about 1892.

Willgodt died in 1905, and his son Alexander took over the business. The early machines were called Odhner's Arithmometer, but from about 1907 the name Original Odhner began being used in order to differentiate them from competitors. After the Russian revolution the company was nationalised, and the production machinery transported to Moscow. Alexander Odhner moved to Gothenburg in Sweden where the company was rebuilt from scratch as Aktiebogalet Original-Odhner. After a few years Russia produced their own Original-Odhner machines with the machinery they confiscated, though in 1928 the machines were rebranded as Felix machines.

Soon after the Original-Odhner company was set up in Sweden, Alexander Odhner died. The leadership of the company changed several times, and in 1923 even fell into the hands of the Scandinavian Bank, who owned it for a decade. Hans Herlitz, the previous director, managed to gather a consortium of people to buy it back from the bank in 1934. Despite all these tumultous changes, the company managed to develop and expand the range of calculator models. From 1931 they started producing adding-listing machines too.

Herlitz died in 1942, after which the company was taken over by Åtvidabergs Industrier who also owned Facit. When the Facit machines were restyled by Sigvard Bernadotte to have a more modern look, the same was done for the Odhner machines. By 1973 the market for mechanical calculators had collapsed, and the companies assets were bought by Electrolux.

Models

The Odhner pinwheel machines made in Russia came in three main types - A (13 digits), B (15 digits), and C (18 digits) and were called Odhner Arithmometers. They were gradually improved over the years, for example the crank was lengthened so that it was easy to turn even when the carriage was shifted to the right.

When production started in Sweden, it was first called the Arithmos, of which five types were produced. There was also the Lusid, a model that could be used for British currency (the consonants in the name Lusid mean L for the £, s for Shillings, and d was commonly used for pence). After that, each type was given an official model number, starting with 6. The table below lists these. The information was mostly gathered from Rechner Lexicon. The options column in the table uses the following letters:
   C = Carry mechanism in the counter
   I = Input display register
   B = Back transfer mechanism.

The many adding-listing machine models are not listed here.

Manuals

Original-Odhner arbeitet für Sie!    (PDF, 3.42 MB or archive.org)
Anleitung für das Rechnen auf der neuen, formgestalteten Original-Odhner
AB Original-Odhner
1956
20 page booklet
127mm × 127mm

This small booklet is the German manual for the Original-Odhner 227. It has no copyright date but on the back it says it was printed in Göteborg in 1956.

Odhner - Eine Addiermaschine die begeistert    (PDF, 1.93 MB or archive.org)
AB Original-Odhner
1959?
12 page booklet
127mm × 127mm

This small booklet is the German manual for the Odhner adding listing machines. It has no copyright date but the illustrations feature model X-11-C-8 or X-11-C-9, so it is from 1959 or later.

Articles and Advertisements

Here are various ads about Odhner machines.

Here is the extensive entry for the Odhner machines in Ernst Martin's 1925 book Die Rechenmaschinen.

Here are various small articles about Odhner machines.

Patents

Here are some of the patents by Odhner relating to the pinwheel calculators.

Links

Rechner Lexicon has a page about Odhner, which has links to many pages for specific models, including Arithmos, and the model 24.
Rechenmaschinen-Illustrated has pictures of many Odhner calculators, and a table of Odhner serial numbers.
Cris Vande Velde has a very early Odhner, a model 24, a page about the prototypes at the Smithsonian, and the Odhner LuSiD.
Rechnen Ohne Strom has a several Odhner models.
W.T.Odhner Memorial Site by Kevin Odhner.
John Wolff has page of various Odhner models, a technical description, and a complete rebuild of the Odhner Model 127.
Christofer Noering's Swedish Typewriter Page has various Odhner models, and a model family tree overview.
Thomas Kirchhof has a Odhner model 27, and a Odhner model 239.
Christian Hamann has a Odhner model 7, a Odhner model 27, and a Odhner model 239
Detlev Bölters has an Odhner Arithmometer type A, an Odhner Arithmos type 1, an Odhner model 29, and many others.

© Copyright 2021 Jaap Scherphuis, mechcalc a t jaapsch d o t net.