Innovation of an iconic design
If you think References 5250, 5359, 5450, and 5550 ended the Advanced Research topic at Patek Philippe, think again. After a six-year hiatus, the research and development department surprised connoisseurs with the release of Reference 5650 in a limited edition of 500 pieces to celebrate the twentieth birthday of the sporty Aquanaut model. This eye-catching white gold wristwatch boasts futuristic watchmaking, beginning with silicon, a material that Patek Philippe co-pioneered and fully mastered. The brand’s engineers successfully optimized the tried-and-tested Spiromax® hairspring over the course of the past several years. A look through a microscope or loupe reveals that the outer “belly” element from 2006 has been joined by a second one. Patented in 2012, this exclusive duo endows the balance with an excellent center of gravity, concentric breathing, and less susceptibility to disturbance caused by positional changes. The duet comprising a classic Gyromax® balance with variable inertia and a Silinvar® hairspring is brilliant thanks to nearly optimal isochronism, meaning that each of the 28,800 hourly semi-oscillations is of equal duration regardless of amplitude and position. Having earned the Patek Philippe Seal, this wristwatch keeps time with a daily rate that remains within the narrow spectrum of -1 and +2 seconds, which is otherwise valid only for tourbillons. And that’s not all: the aperture on the left side of the dial reveals another innovation related to the time-zone display of the Aquanaut Travel Time. The elaborate switching mechanism with numerous levers and beaks for independently resetting the hour hand either forward or backward is re- placed by a complexly shaped and finely crafted corrector with two elastic X-shaped flexure joints. Patek Philippe’s teaching chair at the University of Neuchâtel was involved in its development; the seemingly delicate invention, which has proven itself in outer space, relies on the elasticity of the materials to replace mechanical joints with pivots and leaf springs. The assembly’s constructive height was reduced from 1.45 to 1.24 millimeters, and the ensemble formerly comprising 37 components has now been streamlined to just 12 parts.