Reverso Gyrotourbillon 2

Description

pThe ethereal revolutions of the spherical tourbillon/ppwithin a swivelling case/ppAfter the stunning revelation of the Gyrotourbillon I, Jaeger-LeCoultre is offering the/ppspherical tourbillon a new stage-setting worthy of its technically innovative nature: the/ppswivelling case of the Reverso. Presented in a decorative expression inspired by the finest/ppHaute Horlogerie achievements, this extraordinary watch mechanism overturns longestablished/ppprinciples, since it represents the first time that a wristwatch houses a cylindershaped/ppbalance-spring. Representing a splendid approach to the quest for absolute precision,/ppthe three-dimensional motion of the spherical tourbillon fascinates observers by the/ppexceptional speed of rotation of its two carriages, with the inner one completing a full turn/ppin 18.75 seconds, while the outer one performs a more conventional one-minute turn./ppUniversally acclaimed at the time of its launch barely four years ago, this revolution in the/pptourbillon world now finds an entirely natural aesthetic expression in the Reverso, with its/ppdistinctive shape that further highlights the absolute beauty of this peerless technical/ppaccomplishment./ppWhen the Manufacture Jaeger-LeCoultre first unveiled this avant-garde innovation in 2004, the/ppGyrotourbillon I took the watch industry by storm as the first-ever spherical tourbillon./ppComposed of two carriages mounted on axes set at a 90° angle, this horological microcosm is/ppstill the only mechanical device enabling a wristwatch to break completely free from the/ppdetrimental effects of gravity on its timekeeping precision./ppA new spherical tourbillon/ppEmbodying a mechanical marvel in its own right, the spherical tourbillon and the hundred or so/ppparts composing it exercise an irresistible fascination by the complexity, speed and beauty of its/ppthree-dimensional motion. Eager to enliven still further the entrancing vision provided by this/ppunparalleled watch mechanism, the designers of the Manufacture decided to enhance its already/ppremarkable visual appeal by adding a touch of colour. To achieve this, they suggested that the/pptechnicians perform a daring thermal treatment on one of the most delicate parts of the/ppmechanism, the now famous cylindrical balance-spring with end curves, in order to give it a/ppbluish tint similar to that of the hour, minute and power-reserve hands. And since Jaeger-/ppLeCoultres choices are always simultaneously dictated by both functional and aesthetic criteria,/ppthe arms of the balance were meticulously open-worked to create a slender elegance that also/ppimplies a considerable reduction in weight./pp2 following paragraphs (The barrel…. and The extraordinary….) are taken out here and used/pplater in the text/ppA key feature of the Gyrotourbilon 2: the cylindrical balance-spring with end curves/ppThe second version of the Gyrotourbillon is distinguished by an essential organ: the presence of/ppa cylinder-shaped balance-spring with end curves. This component was invented by English/ppwatchmaker John Arnold, who had it patented in 1782. Due to the complexity involved in its/ppproduction and the difficulties implied by attempts to miniaturise it, this ingenious discovery/ppwhich guarantees a regular and perfectly isochronous development of the balance-spring was/ppreserved exclusively for marine chronometers and a few generously sized pocket-watches. It/ppthus appeared doomed never to drive a wristworn mechanism. Innovative watchmakers chafed/ppat this regrettable situation, since its rating characteristics are unanimously considered to be/ppinfinitely better than those of a flat balance-spring./ppNonetheless, all obstacles and pitfalls, however insurmountable they might appear, inevitably/ppspur the engineers and watchmakers of the Manufacture to decisive action. The latter were able/ppto grasp the opportunity represented by the spherical tourbillon and to present a cylindrical/ppbalance-spring nestling at the heart of a wristwatch. Combined with the specific advantages of/ppthe spherical tourbillon, this innovation represents a breakthrough in the field of accuracy and/pppaves the way for a level of rating precision that is simply unprecedented on a timepiece/ppdesigned to follow its wearers arm movements./ppThe extraordinary complexity of the spherical tourbillon/ppEmbodying a major step forward in the history of mechanical horology, the spherical tourbillon/ppoffers wristwatches the same advantages that the classic Breguet tourbillon had brought to/pppocket-watches. Since the late 18th century, the tourbillon mechanism has freed watch/ppmovements from the influence of gravity on the regulating organ and its adverse effects on/ppprecision. This prodigiously designed mechanism serves its true purpose in a pocket-watch,/ppwhich generally sits upright in a waistcoat pocket. However, the usefulness of a traditional/pptourbillon is far less obvious in a wristwatch, which is usually worn in a horizontal position. This/ppparticular situation requires the watchmaker to perform adjustments in several positions in/pporder to determine a satisfactory average rate./ppThrough its conception and its construction built on two axes set at a 90° angle, the spherical/pptourbillon is the only device that compensates for the effects of gravity in all positions./ppNonetheless, actually producing it called for the use of ultra-light high-tech materials in order to/ppcreate a mechanism able to simultaneously drive the rotation of both carriages. Their speeds of/pprotation are so fast – one turn per minute for the outer carriage and one revolution in just/pp18.75 seconds for the inner carriage – that the balance maintains constant amplitude, whichever/ppway it is oriented. For the first time in watchmaking history, the exactness of a watch is thus/ppentirely independent of the position of the timepiece itself. Loyal to the uncompromising/ppprinciples that govern each of its decisions, Jaeger-LeCoultre refused to take the easy path to/ppachieving this result by reducing the size of the balance or the frequency of its oscillations. In/pporder to guarantee infallible accuracy, the Reveros Gyrotourbillon 2 is equipped with a large/ppgold balance that is fairly insensitive to vibrations or shocks, has an inertia of 12.5 mgxcm2 and/ppimperturbably oscillates at a rate of 28,800 vibrations per hour. In an ultimate touch of luxury/ppand in order to avoid any alteration in the rating in case of impacts, adjustments are made by/ppmeans of gold inertia-blocks arranged around the rim of the balance./ppAn absolute Reverso, for a new dimension in time measurements/ppIn terms of its horological functions, the Reverso Gyrotourbillon 2 displays the time by means of/pptwo flame-blued steel hands moving over an off-centred sapphire subdial. A fine engraving on/ppthe wheel to the left of the dial enables one to read off the time on a 24-hour scale. Meanwhile,/ppthe seconds are indicated by a blue index that is actually part of the outer tourbillon carriage./ppOn the back, a hand integrated within the movement indicates the power reserve on a sectorshaped/ppbridge./ppNonetheless, at the very moment when a Jaeger-LeCoultre watch appears to have revealed its/ppessential characteristics, a new element consistently overturns the global view that an attentive/ppobserver is struggling to gain. For this particular model, in order to house the manually-wound/ppCalibre 174, the engineers of the Manufacture had to design an entirely new swivel case that/ppnonetheless complied with the inimitable DNA of the Reverso. By the very nature of its/ppoperating principle, the spherical tourbillon calls for a thicker type of envelope in order to/ppoperate in perfect freedom and security. […]

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