Close Up: IWC Ingenieur Constant-Force Tourbillon

A flagship of the Ingenieur Collection, the Constant-Force Tourbillon watch was finally delivered to IWC Schaffhausen’s Moscow boutique, where Haute Time Russia recently had the chance to get an exclusive look at this watch.

Despite the fact that it costs more than 10 million rubles (US$290,000), the brand’s loyal costumers have already been fitted with this model, or at least they’re making plans to get their hands on it!

The Constant-Force Tourbillon’s features IWC’s patented constant-force mechanism integrated into a tourbillon, a mechanism which was first used in the Portuguese Sidérale Scafusia three years earlier (the model received the title of the most complicated watch ever produced).

The goal of the constant-force mechanism is to ensure the amplitude of the balance remains almost constant. The 94800-calibre basic movement features two barrels, which provide the energy for the higher torque required to drive the constant-force tourbillon. When you tighten the winding barrel, energy is stored temporarily in the balance spring from where it is transferred to the escape wheel. This puts the balance spring under tension once a second, while the seconds hand in the tourbillon advances in one-second jumps.

IWC engineers have achieved the utmost precision with the Constant-Force Tourbillon, which boasts an extremely regular and precise rate over a period of at least 48 hours. After two days, the movement switches from constant-force mode to normal mode.

This switch from constant-force mode to normal mode can be seen visually via the seconds hand attached to the tourbillon cage, which starts to advance at intervals of one-fifth of a second. As you might guess, the Constant-Force Tourbillon boasts an impressive power reserve, at 96 hours.

Aside from the tourbillon, the timepiece boasts a moon phase display and a power reserve display. The case is made of platinum and ceramic. While the piece is quite big, it still sits nicely on the wrist; after all, ergonomics are a hallmark of all Ingenieur models. The Constant-Force Tourbillon is part of a limited release of 50 pieces, №12 of which is now in Moscow.

Photo credit: Chronoscope.ru.