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chronomètre à résonance 56
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chronomètre à résonance calibre fpjourne 1499-2 mobile escapement-holder 2 barrels and 2 independent gear-trains 32mm in diameter and 4.80mm thick straight-line lever escapement dedicated 4-arm balance with inertial adjustment escapement frequency of 21,600 vph 267 components excluding the exterior 36 jewels plates and bridges in 18-carat pink gold 40-hour power reserve 58
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chronomètre à résonance françois-paul journe pays tribute to the research conducted on resonance by the great 18th century watchmakers with the presentation of the first wristwatch resonance chronometer first unveiled in the year 2000 this watch represents one of the wildest challenges ever in the field of the mechanical watch using the natural phenomenon of resonance this mechanism revolutionises established standards and offers a previously unmatched degree of precision in mechanical wristwatches the first research on the phenomenon of research in horological science dates back to the 18th century with watchmakers such as antide janvier 1840 and abraham-louis breguet 1823 they observed the negative effects of these waves on clocks and then conducted each in his own way research into ways of using this phenomenon in the operating of regulators 60
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chronomètre à résonance two centuries later françois-paul journe took up the challenge with a first creation in the form of a pocket-watch which did not yet perform according to his expectations it would take fifteen more years of work for the watchmaker to gain the maturity and the experience to enable him to present an exclusive world première the first resonance wristwatch he devised developed and built this movement to meet the demands of actual wear on the wrist and thereby provide chronometric performance driven to extremes each of the two balances alternately serves as exciter and resonator when the two balances are in motion they enter into sympathy due to the effect of the resonance and begin naturally beating in opposition the two balances thus rest against each other giving more inertia to their movement nonetheless this harmony is possible only if the difference in frequency between them does not exceed five seconds per day of cumulated difference in six situations adjustin
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the deadbeat seconds device or the art of making time stand still towards the late 17th century as clocks were becoming increasingly precise watchmakers added a hand finally enabling them to measure seconds these clocks which became pendulum clocks thanks to the invention of the pendular balance by the dutch watchmaker huygens were almost naturally equipped with a 1 metre-long balance with a period of 1 second the dial was marked out into 60 subdivisions so that the hand could jump from one second to the next when the first watches indicating seconds were made some 18th century watchmakers wanted to achieve the same visual effect as on clocks to do so they invented systems extending the period of the balances the best-known being the crown-wheel escapement with pendulum or the huge balance by mr pouzait nonetheless these systems were rapidly abandoned since they were detrimental to precision thus without an additional system the hand started to beat out the half-second the most
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the constant-force device from ancient times humankind has constantly attempted to measure time by dividing it into equal fractions and inventing the notion of isochronism only with the arrival of the first mechanical clocks did specialists begin to seek a means of equalising the force reaching the escapement the balance-spring did not yet exist and the so-called foliot balance had an irregular beat due to the arrival of a force varying because of the imperfections of the gearing at the time clocks were equipped with just one hand which completed a revolution once every 12 hours since their degree of imprecision did not permit the measurement of minutes after the invention of the mainspring which would enable the construction of table-clocks 15th century watchmaker jobst bürgi had the idea of adding an extra gear representing an independent system wound in short spurts by the mainspring the escapement thus ensured a more constant flow and enabled an autonomy of several months this w
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