TOURBOGRAPH PERPETUAL « POUR LE MÉRITE »
The fifth masterpiece in A. Lange & Söhne’s “Pour le Mérite” series combines the fusée-and-chain transmission with a tourbillon, a chronograph, a rattrapante function and a perpetual calendar. The combination of these five complications makes the TOURBOGRAPH PERPETUAL “Pour le Mérite” a peerless timepiece.
The integration of a perpetual calendar in the TOURBOGRAPH PERPETUAL “Pour le Mérite” presented the engineers of the Saxon manufactory with a formidable challenge: to orchestrate the interaction of the complex mechanisms in such a way that mechanical conflicts or unwanted energy losses could be prevented. In this project, the perpetual calendar mechanism had to be built around the tourbillon. Consequently, only about two thirds of the movement surface were available, and this necessitated a redesign of the basic calibre. At the same time, the developers did not want to noticeably increase the height of the movement.
Of the 684 parts of the new L133.1 manufacture calibre, no fewer than 206 constitute the perpetual calendar with its analogue displays. It will correctly indicate the duration of each month until 2100. A one-time correction will be needed on the last day of February in this secular year. From then on, the calendar will again be correctly calibrated for the next hundred years. It has three subsidiary dials. The date at 12 o’clock and the day at 9 o’clock are indicated with rhodiumed gold hands. The month and leap year are both displayed at 3 o’clock. The upper half of the analogue date also accommodates the moon-phase display which is calculated to remain accurate for 122.6 years. Its deep-blue disc is made of solid gold. During the development of the calendar module to be built around the tourbillon, great emphasis was placed on space-saving architecture.
The combination of a perpetual calendar with a split-seconds chronograph is very rare. Power management is an especially challenging undertaking. In particular, the simultaneous use of several functions calls for mechanical ingenuity, for instance when the calendar indications advance around midnight and the stopwatch function is used at the same time. Assembling such a movement requires considerable experience and exceptional sensitivity when adjusting and harmonising the mechanisms.
The TOURBOGRAPH PERPETUAL “Pour le Mérite” is being crafted in a limited edition of only 50 platinum-cased watches. The finish of the manufacture calibre complies with the highest standards of Saxon watchmaking artistry. Thermally blued screws, screwed gold chatons, bridges and plates made of untreated German silver and decorated with Glashütte ribbing and perlage as well as the hand-engraved chronograph bridge round out the highlights of the classic complication.
Limited Edition 50 pieces