Breguet / Classic Tourbillon Part.3

The tourbillon, invented by Abraham-Louis Breguet in 1795, was a watchmaker's dream mechanism. However, Breguet himself only produced 35 pocket watches, and it took nearly two centuries for it to be incorporated into a wristwatch. It was the Swatch Group that made the tourbillon a reality. The late Nicolas G. Hayek, who was then president of the Swatch Group, brought the tourbillon tradition back to Breguet with incredible passion.

CLASSIQUE TOURBILLON
EXTRA-PLAT AUTOMATIQUE 5367
Thin automatic tourbillon with peripheral rotor

　Since joining the Swatch Group, Breguet has shifted its focus to creating timepieces that combine aesthetics with practicality. Or, more accurately, it has returned to the days of Abraham-Louis Breguet. This includes tourbillons, and almost every year, the company has added unique and practical tourbillons to its lineup.

　If we were to pick a watch that symbolizes this at the moment, it would be the ultra-thin Classic Tourbillon Extra-Thin Automatic 5367. In addition to the high magnetic resistance and high precision provided by its silicon balance spring and escapement, this model boasts a long power reserve of approximately 80 hours, a thin case that could easily be mistaken for a dress watch, and a very well-made Grand Feu enamel dial.

　Despite being an automatic watch with a peripheral rotor, it boasts a long power reserve thanks to a thin barrel core that accommodates the longest possible mainspring. Furthermore, by adopting a structure that supports the barrel horizontally, rather than vertically, it was possible to use a mainspring with high torque (i.e., a wide mainspring) despite the thin barrel. The head of the technical department explains, "The idea of ​​a thin barrel dates back 200 years. However, because the mainspring's torque is 550 g/mm2, we were able to increase the frequency to 1600 vph instead of the usual 8800 vph, and we also succeeded in increasing the balance wheel's moment of inertia to 6.3 mg/mm2. The daily rate is within the range of -1 to +3 seconds per day, and the power reserve is approximately 80 hours." These are performances that are hard to believe for an ultra-thin tourbillon.

　Breguet once held the view that "if you put an automatic tourbillon on a two-hand watch, the thickness should be limited to 4mm. It's impossible to make it any thinner than that." This is why the company has long distanced itself from thin tourbillons. However, technological advances have made even the impossible possible.

CLASSIQUE DOUBLE TOURBILLON 5345
The gear train itself rotates every 12 hours
Carousel-style double tourbillon

　The "Classique Double Tourbillon 5347," released by Breguet in 2006, featured a tourbillon with two barrels and a base supporting two tourbillons that rotated once every 12 hours. Breguet obtained various patents (CH697523B1, CH695797A5, etc.) in the development of this model, making it impossible for other companies to imitate it at this time. 14 years after its release, this model remains the pinnacle of Breguet tourbillons.

　The "Classique Double Tourbillon 5345 Quai de l'Horloge," newly announced in September 2020, is a model that removes the dial and skeletonizes the movement. Achieving a balanced weight is extremely difficult for a double tourbillon, whose movement itself rotates. Furthermore, Breguet has added engraving and hollowed out the movement. While the 5367 featured on page 104 offers a high level of aesthetics and practicality, this model is sure to push the boundaries of what's possible with a tourbillon.

　To ensure that the tourbillon movement itself could accurately indicate time, Breguet not only perfectly balanced the weight of the rotor, but also added a mechanism to minimize play in the gears, and employed a mechanism to stop winding one barrel until it was fully wound.

　As far as I can see, the skeletonized double tourbillon, including the finish, is the pinnacle of Breguet. The smoothly rotating 12-hour tourbillon and outstanding finish. Its almost excessive presence is fitting for a flagship from Breguet, the inventor of the tourbillon. This year marks more than 20 years since Breguet joined the Swatch Group. This model is a symbol of the greatly changed modern Breguet.