At the upcoming Salon International de la Haute Horlogerie (SIHH 2011), French jeweler Cartier is going to present a whole bunch of interesting timepieces. The new Calibre de Cartier Astrotourbillon Calibre 9451 MC limited edition hand-wound watch is one of them. After the five years of careful planning and precise development, Cartier presented its new masterpiece produced in a limited edition of only 100 individually numbered pieces.
Well, to be more precise this one is not a completely new watch. Rather, it is the same Rotonde de Cartier Astrotourbillon timekeeper that was presented in the beginning of the year at SIHH 2010 show. However this time its Calibre 9451 MC manual-winding movement is installed into a 47 mm Calibre de Cartier case made of titanium. It sports a rather unusual tourbillon complication with its carriage positioned above the movement and between two plains of the three-dimensional dial, while most traditional tourbillon movements usually keep the component firmly integrated into their structure.
The 9451 MC movement features a tourbillon carriage that contains the escapement organs and balance spring. As in a classic tourbillon, the carriage is driven by the third gear-wheel. The escapement pinion turns around a fixed seconds wheel (the fourth wheel of the gear train) in order to drive the escapement. Yet, this spectacular tourbillon, named the Astrotourbillon, has several special features that make it unique.
First, its carriage is positioned in the centre of the movement and thus relies on a special rotational axis. This, of course, involved redesigning the entire gear train, from the twin barrels of the movement to the hours and minutes displays. Second, and this is what creates the Astrotourbillon’s striking visual effect, the balance and the escape wheel are not on the same rotational axis as the carriage. They are set to one side of the carriage, in linear alignment with its rotational axis. Lastly, the tourbillon carriage is positioned “above” the movement between two dials, instead of being directly integrated into the movement like a classic tourbillon. This central construction is unusual and has both aesthetic and technical consequences.
The Calibre de Cartier Astrotourbillon Calibre 9451 MC has sapphire crystal front and case-back. The delicate movements of the inner mechanism are visible trough the transparent back. The piece is water resistant up to 30 meters, and suitable for everyday use. The Astrotourbillon movement is manually wind, and provides a power reserve of approximately 48 hours.