Orbital Tourbillon Watch
The Orbital Tourbillon, the first of the JEAN DUNAND Unique Pieces, is distinguished by its two simultaneous rotation speeds: the flying tourbillon turns on itself at the rate of the minute, while making a complete revolution around the dial every hour. This is an unprecedented achievement in watchmaking. On the sides of the case, two windows allow one to admire the movement, the other to discover an innovative power reserve indicator. The moon phases are displayed on the background.
This extraordinary movement is patented and the power reserve indicator is currently the subject of a patent application.
Retesting the tourbillon as a precision device
The Io 200 movement (named after Jupiter’s moon), built by Christophe Claret, confuses the opinion of his peers who considered that an orbital vortex was impossible to achieve. It gives the tourbillon back its original role as a precision device. Synchronization tests have implied that the combined rotation of the tourbillon and the movement improves gait stability significantly.
Wheels in wheels
The barrel and the flying tourbillon (opposed to each other), classified between two plates kept separated by pillars and guided by ball bearings, orbit around the center. The upper plate in revolution, the opening of which reveals the tourbillon, acts as a dial. To be better admired, the tourbillon was placed as high as possible.
The barrel relaxes against a fixed central pinion, around listening it rotates accompanied by the tourbillon. When in orbit, the tourbillon cage performs one rotation per minute against a wheel of fixed circumference thanks to a cog. This elegant configuration made it possible to reduce the number of pivots on ruby to 14, thus limiting friction substantially.
How to wind up and set the time for a rotating movement?
The conventional crown crossing the caseband at 3 o’clock being obviously inapplicable, it took Christophe Claret nearly two years to develop the mechanical solutions for winding and setting the time for a rotating movement including the barrel-motor spring assembly is never in the same place.
The chosen solution, unprecedented in watchmaking, allows the movement to be wound up and set to time vertically, passing through its central axis. A folding key, fixed in the back of the case, replaces the crown. Raising the key ring engages a central wheel on ball bearings, which drives the ratchet to wind the barrel spring. Pulling out the key engages the mechanism for adjusting the hour and minute hands which can be adjusted in either direction. The time is read in a classic way thanks to the fixed hour circle, in the form of an inclined flange attached to the case.
An open window on the heart of the movement
The winding key and the moon phase indicator give the back of the watch all its originality, thus distinguishing it from the conventional view of the movement through a sapphire crystal. The absence of a traditional crown at 3 o’clock also made it possible to offer a fascinating side view of the rotating mechanisms thanks to the window cut into the caseband at 9 o’clock.
Principles of style and construction
JEAN DUNAND Unique Pieces are manufactured exclusively to order. The aesthetics of the watch are always inspired by the ideals of Art Deco, namely simple geometries, functional design and fine craftsmanship resorting to the use of the most precious and rare materials. Each timepiece signed JEAN DUNAND must be a masterpiece of contemporary art. The enlightened collector is thus assured of owning a truly unique piece of an unequalled level of exclusivity.
The finishes of a watch are an essential dimension of the art of watchmaking and must, as such, be impeccable. The graining, chamfering and polishing of each part of the movement are carried out entirely by hand. For example, the edge of a part having an acute interior angle cannot be bevelled using a machine – in this case we speak of a “re-entrant corner”. Likewise, the decoration of the case as well as the terminations are carried out according to the most stringent quality requirements.