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Best Tourbillon 2022: Grand Seiko Kodo Constant-Force Tourbillon

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It has been a phenomenal year for the watch world. To round off 2022, we are celebrating the hits, the wonders, the visionaries and all the people in watchmaking who have made it so memorable in our annual Revolution Awards and Power Lists.

The Tourbillon remains a great indicator of technical ability and artistic expression, and this year, the winner was clear. The dramatic Kodo Constant-Force Tourbillon from Grand Seiko.

The Grand Seiko Kodo Constant-Force Tourbillon is a clear winner as it combines a stop-seconds tourbillon with a constant-force mechanism in a format that is optimal and rarely executed. Since François-Paul Journe introduced the first tourbillon wristwatch with a remontoir in 1991, there have been a number of watches on the market that combine a torque regulating mechanism with a tourbillon. These come in the form of the fusée and chain, which is located at the power source, or the remontoir d’égalité, which is typically arranged along the gear train. The Grand Seiko Kodo Constant-Force Tourbillon, however, is among the rare few in the market that has a cage-mounted remontoir.

Grand Seiko Kodo Constant-force Tourbillon

In fact, the tourbillon and remontoir are constructed in a co-axial configuration in the Kodo Constant-Force Tourbillon. The remontoir, which is recharged by the gear train precisely every second, is built with its own cage that houses the tourbillon carriage. The theoretical advantage of a remontoir that is integrated with the tourbillon is that it delivers impulse directly to the tourbillon, eliminating a host of other variables that could cause fluctuations in rate had it been located at an earlier stage in the transmission system. The entire remontoir mechanism is made up of a remontoir wheel, a ratchet-shaped stop wheel and a remontoir spring — all of which are located at the base — as well as a cage, on which a seconds hand is mounted. The remontoir wheel and the stop wheel are driven by the gear train. Right above the remontoir spring and at the bottom of the tourbillon cage is a stopper with a jewel pallet at its tip that stops the ratchet-shaped stop wheel every second, creating a snapping motion. Each time it snaps forward, it releases the remontoir spring. This causes the distinct ticking motion of the remontoir wheel and cage, allowing it to double as a deadbeat seconds indicator.
Beyond that, the pallet fork and escape wheel are fabricated using an additive lithography technique, allowing the components to be fabricated with extreme precision, resulting in its intricate, skeletonized geometries that are lighter to reduce inertia. This aids in achieving a beat rate of 28,800vph or 4Hz, which is higher than the standard frequency in most tourbillon movements.