What is a 400 day clock



Here is something about the history of the

"Annual clocks"

A."Annual clocks" are commonly referred to as mechanical clocks that only need to be wound up once in 400 days. Annual clocks do not have a battery and quartz drive, but a mechanical movement and a so-called rotary pendulum or torsion pendulum. This causes the very slow progression of the escapement with 8 to 16 periods in the MINUTE!

A.Other "normal" mechanical clocks (e.g. grandfather clocks) are around 60 periods per minute, depending on the length of the pendulum. Wall clocks and table or mantel clocks have an even faster period, depending on the length of the pendulum.

D.he annual clocks, also known as 400-day clocks, had their great time at the end of the 19th century in Germany and, after the decline of this type of clock, it was not until the 1950s as an export hit to the USA and the Middle and Far East.

I.In the USA, the "annual clock" enjoyed great popularity, it was often given away on anniversaries (wedding, birthday, name day, etc.) and then wound up in a small ceremony once a year on this day and then faithfully again for a year counting the time. They got the name "Anniversary Clock".


HHere is the development of the "clock of the year", whose home country was Germany, although the first patents came from America. But read:

HHere is the story of the annual clocks, very briefly and incompletely:

3 patents from the USA in the years 1841, 1850 and 1852 from the well-known watch areas of the USA from 3 different watchmakers.

None of these patents were converted into a working watch.

In 1876 an American, John W. Hile, appears, whose patent is more likely to be described as a “year clock” in today's sense.

E.It is possible that Anton Harder, born in Ransen / Oder, today Poland, knew of this patent (whether he was ever in America is questionable). In any case, Harder teamed up with the watchmaker Lorenz Jehlen in Säckingen in 1879, because L. Jehlen held the patent for an adjustable rotary pendulum, which was suitable for slow-speed runners, but NOT for a watch like Harder.

L.Then L. Jehlen died in 1879 and the widow Jehlen transferred the patent for the rotary pendulum to A. Harder.

F.Harder read some patents for this now complete watch - registered in Austria-Hungary in 1880 and in the USA in 1882. No patent can be proven for Germany during this time.

A.The company A. Willmann / Freiburg - Schlesien was the first watchmaker to produce annual watches in Germany based on the American patent from Harder. According to the documents of the later Gustav Becker company, it should have been around 340 pieces. However, production was discontinued after these "attempts" because it was too unreliable and absolutely inaccurate and therefore unsuitable for series production. The rumor persists that the Gustav Becker company also made annual clocks. But that's just a rumor! In response to his inquiry, the company owner told A. Harde "... we (Gustav Becker) are not damaging our good reputation with these toys ..."! All annual clocks manufactured with the brand "GB" and the Medaille de Or come from the machines of VFU AG from 1900.

A. Harder is also said to have manufactured a few models himself, which are marked with "Harder / Ransen bei Steinau a / O". That too belongs in the realm of fable. Harder was not a watchmaker, nor was he a precision mechanic. He was the administrator of a country estate! are. The patent stated on these watches (Harder Ransen at Steinau a / O / D.R. Patent No. 2437) relates to the adjustable rotary pendulum from Jehlen / / Säckingen!

S.Oh, and now A. Harder comes into the black forest. It's not very far from Säckingen. First Harder tries his luck at the brass foundry Siedle. Siedle manufactured cast clock parts - wheels, plates, bells, etc. Siedle cannot help Harder because he only produces parts in his factory and does not have any watch production. But he knows 4 watchmakers in Triberg who have just started their own business. Siedle refers Harder to this company: Gebr. Wintermantel & Cie. The company brand: GW & Cie. Harder speaks to the 4 partners of Wintermantel & Cie. All 4 previously worked for the Fortuna company and after its bankruptcy bought into Wintermantel. It was here in 1881 that the watchmaker August Schatz developed the really first functioning annual clock based on the A. Harder patent (with Graham escapement). August Schatz took over the majority of Wintermantel & Cie. and renamed the company for the first time (1882) to "Annual Clock Factory" and shifted almost exclusively to the production of annual clocks (DeGruyter had financed the machines and bought Harder's patents to be on the safe side).

VFrom then on, the “Jahresuhrenfabrik” was the market leader in annual clocks, which, however, were almost exclusively produced for export (DeGruyter). This was also due to the fact that the patents for the clock and the pendulum were with DeGruyter and only after DeGruyter no longer wanted to or could not pay the patent fees, these were released around 1900 and many other large watch manufacturers jumped on this "train".

E.Some of the manufacturers have attempted to penetrate this market earlier with their own patents (round plates, pin gears, cylinder escapement, etc.). But the clocks were too sensitive and too imprecise. There were patents from other manufacturers mainly on the rotary pendulum.

KA watch manufacturer produced all parts of its watches. Dials were bought in, and the case was usually manufactured by the sales partner according to customer requirements. The movements were also very often sold to well-known watchmakers in relatively large numbers. One example is Anton Huber, purveyor to the court in Munich. A. Huber had the patent for a compensating rotary pendulum (1902) but none for an annual clockwork. So he obtained the movements, for example, from the Jahresuhrenfabrik, KIENZLE and BADUF and assembled his clocks himself and also sold them under his name.


Und to accuracy:

A.In the beginning, the available steel springs were used as pendulum springs. These had the major disadvantage that they reacted very sensitively to temperature fluctuations (warm = clock was slowing down, cold = clock was going up). These pendulum springs also rusted quickly.

I.In these times so-called compensation pendulums were developed (mercury, bimetal, pendulum springs made of two metals with adjustment, etc.). But nothing brought real success. Attempts with bronze springs (in the 1920s - 1930s) were doomed to failure, as spring bronze had even worse temperature properties than steel springs. Only they didn't rust.

ZAt the end of the 1930s, alloy steels were developed, which then quickly found their way into watchmaking. The pendulum springs were now also made from these new alloys, making the annual clocks so accurate that they could keep up with any wall or grandfather clock.

L.There is only one problem to this day and that is the reason why annual clocks are still falsely decried as "inaccurate": A wall or grandfather clock is wound once a week or once a month and without any emotion any preceding or following balanced.

D.he rate error, e.g. 1/2 minute a week, is absolutely fine for such watches. But with an annual clock, this error will add up over 1 year and will then add up to a whopping 26 minutes the next time it is wound up (that's too much, of course.


ZFinally, a comment on what kind of "annual clocks" actually existed and still exist.

D.a are first and foremost the normal, mechanical annual clocks with a 400-day movement. Then there is a small series from the 50s as a 1000-day watch exclusively from the company August Schatz and Sons (see under "My watches"). There are also annual clocks with complications. The best known come from KAISER's production, with mod phase display. Some manufacturers tried their hand at watches with a date display and striking mechanisms, but without great success. But there are still a few such clocks and these are the real treasures among the annual clocks. There are also 30-day watches and those with a 3-month movement.


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Quote from

"SCHATZ 100 Years of the Annual Clock Factory GmbH Aug. Schatz & Soehne"
Company history 1881 - 1981

The name “Jahresuhr” refers to a type of clock that is equipped with a so-called torsion pendulum.
The special thing about it is the unusually long running time of 400 days.
This type of watch was invented in the USA in the mid-19th century, in the watch regions of Connecticut and New Jersey.
Samuel B. Terry of Plymont, Connecticut, claimed a patent for a clock with a torsion pendulum regulator in 1852.

None of these patents and developments could be used for series production.
Only the Black Forest watchmaker August Schatz succeeded in doing this.

In 1883 Mr. Harder sold the patent for the J. Uhr to Mr. du Gruyter in Amsterdam, whereupon we started the manufacture of weight regulators.
tasks and exclusively made J. watches for Mr. Gruyter .....

Quote end

The company "Jahresuhren-Fabrik" under August Schatz was the first manufacturer of annual clocks in series (on behalf of the godparent owners Harder and then du Gruyter) in Germany. Beginning in 1881 and unfortunately ended in 1986.



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Status: 05.09.18

(c) Rolf-Dieter Reichert 2018