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Hans Ulrich Klingenberg and the Vacuum Chronometer

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In 1921, British railway engineer William Hamilton and horologist Frank Hope-Jones designed the Shortt-Synchronome free pendulum clock with the aim of reducing air resistance and producing a highly accurate timepiece. They did this by linking a “slave” synchronome clock on which the time was displayed via electromagnets to a “master” pendulum which swung free in a vacuum tank. These were the most accurate pendulum clocks ever commercially produced - accurate to about 1 second per year, with only 1 beat to the second - and in 1926 a clock of this type was used to detect tiny seasonal changes in the earth’s rotation rate. Only about 100 of these clocks were made and it would not be until the arrival of quartz technology that such clocks were surpassed in accuracy.




A Shortt-Synchronome clock, no. 84 and dating to about 1925, caption heading from auction catalogue: William Hamilton Shortt N. 84 An English mahogany, copper and brass free pendulum observatory regulato. This was Lot 2 in Christies London sale (no. 7012)of "Magnificent Clocks" held on 15 September 2004 and realised a price of £40,630 (pic from christies.com):






The idea then of creating a vacuum within a timepiece was not a new one when it was revived and developed for use inside wristwatches, although when this notion did later receive attention, the reduction of air resistance was not the major aim. Thus it was that in about 1960, Hans Ulrich Klingenberg, a young salesman for Glycine, came up with the idea of evacuating a watch case, primarily with the intention of removing dust, moisture, contaminants and oxygen, and preventing their re-entry; the removal of air was also seen as having the benefit of limiting temperature differences inside the watch. It should be explained at this point that water resistance itself in a watch is not the equivalent of creating a vacuum because water molecules are much larger than air molecules, so are more easily blocked - it all depends on the performance of gaskets and the quality of seal. 

Klingenberg designed a one-piece watch case with a flat mineral (later sapphire) crystal which was held against a thick O-ring gasket by specially designed bezel clamps. This was combined with an oversized crown fitted with three O-rings. To accompany this design, by which an 80% void was possible, Klingenberg also developed a special hand-held device that enabled the vacuum inside the watch to be re-established after the watch had been serviced - recommending a service interval of between 5 and 8 years.

Klingenberg’s vacuum system was initially used at Glycine; the Glycine Vacuum range was introduced in 1962 and utilised various movements, mainly the ETA 2638 (and it seems, the ETA 2472) but on 5 January 1966, taking advantage of the repeal of the protectionist Statut Horloger that had made setting up a watch company in Switzerland difficult, Klingenberg established his own company, the Vacuum Chronometer Corporation, in Bienne. This company co-operated with a number of case-makers and watchmaking companies, producing vacuum watches for a number of brands including Glycine, Croton, Waltham and Dugena, all recognisable by the bezel clamps at 12 and 6 o,clock. Note that the use of the word “chronometer” in the company title has caused some confusion over the years, with doubts expressed as to Klingenberg’s right to use this term. A few more words will be said about this below; as for Glycine, their vacuum watches were produced up to 1972.




1960s Advert for the Glycine vacuum watch (pic from worthpoint.com), and the Glycine watchmaker's hand-pump for use when servicing vacuum watches - see text (pics from i.imgur.com):

Image result for glycine vacuum chronometer images







In 1967 [see NB at end of this topic text], Klingenberg changed the name of his company to Century Time Gems AG and produced watches under his own name. The logo he chose was a stylised illustration of the “Magdeburg Hemispheres”, a 17th century experiment designed to show the power of air pressure whereby two copper bowls could not be separated by two teams of eight carthorses once the air had been removed. In order to comply with the “chronometer” part of the original company name, it is said that Klingenberg paid extra to develop and obtain all the necessary adjustments for COSC to test the watches fully assembled and evacuated rather than as de-cased movements - a somewhat radical approach for the time. Also, in pursuit of greater accuracy, in the period subsequent to the change in company name, Klingenberg preferred to use high-beat (36,000 beats per hour) movements in his Century vacuum watches such as the ETA 2837.




A mid-1960s Glycine vacuum watch powered by a chronometer-standard high beat movement (pic from iguanasell-pics.com):





The use of an air-free environment inside a watch may have had some impact on improving accuracy over the long term, and on achieving longer service intervals. However, the watch industry as a whole did not prove to be receptive to Klingenberg’s innovation and it was not to be developed further by other manufacturers. To some extent, the Quartz Crisis was partly to blame for this because the arrival of highly accurate quartz movements at ever-decreasing prices in the 1970s swept away any sense of necessity for such a feature as vacuum cases. Ironically, the less bulky quartz movements offered Klingenberg greater opportunities in terms of creating his perfect watch and Century Time Gems survived the Quartz Crisis. Klingenberg himself continued to search for improvements in case materials and construction, being one of the first manufacturers to use boron carbide as a case material before moving on to cases made from corundum (sapphire); applying another of his patents, Klingenberg produced a diamond-facetted “Megalith” case created by fusing two discs of sapphire together, and his later work pre-empted watch companies such as Richard Mille and Hublot by decades.



A rare Waltham Ruby Vac automatic vacuum watch from the late 1960s by Century Time Gems Ltd (and bearing the "Magdeburg" Century Time Gems logo), and a Japanese advert for Waltham vacuum watches from 1968 (pics from i.imgur.com):







Today, Century Time Gems Ltd is based at Nidau, Switzerland and the company is headed by one of the founder’s sons, Philip W A Klingenberg. The company is a full member of the Federation of the Swiss Watch Industry FH.

NB: that according to "Business Monitor", both Century Time Gems AG and The Vacuum Chronometer Corporation AG are still active and are essentially the mirror images of a single organization, both in Nidau, Bern, Switzerland; both companies were apparently registered in January 1966. I also have to report that one source has stated that Century Time Gems Ltd became the title of the Vacuum Chronometer Corporation in 1975; looking at the extant watches, however, indicates that this date is too late.




An important  Croton (100th anniversary) vacuum chronometer also branded for Century Time Gems Ltd. and dating to 1978. 35.5 mm (excl. crown) stainless steel case with solid 14 carat gold bezel and retaining blocks, bevelled mineral glass crystal, and powered by a high frequency, 36,000 A/h, ball bearing rotor ETA 2738R movement (pics from assets.catawiki.com):







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Interesting topic, Honour. :thumbsup:

The concept of encasing a timepiece in a vacuum can be traced back to an idea by Italian clockmaker Antimo Tempera (1668).

Englishman John Harrison also worked on the idea when building his marine chronometers.


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