Audemars Piguet took the lead in solving one of the oldest problems in the watchmaking industry: the double balance wheel inside the Royal Oak skeleton The balance wheel is often regarded as the heart of a mechanical watch. The balance swings back and forth because it is connected to the hairspring, which is a flat metal spiral with a slight elasticity. Most balance springs are fixed at the center and outer limits of the spiral. Due to the two fixed endpoints, they cannot breathe concentrically. When the watch is placed vertically and gravity acts on the balance spring, this problem will be more serious, and even make the balance spring…