The pursuit of perfect timekeeping has driven watchmakers for centuries. While the mechanical watch is a marvel of miniature engineering, it faces an inherent challenge: maintaining consistent accuracy as its power source depletes. The mainspring, when fully wound, delivers strong torque, but this force diminishes as it unwinds. This fluctuation in energy delivery directly impacts the balance wheel's amplitude, leading to variations in the watch's rate and, ultimately, its precision.
The Quest for Unwavering Precision
This fundamental problem has led horologists on a quest for what is known as "constant force." A constant force escapement aims to isolate the regulating organ (the balance wheel and balance spring) from the inconsistent torque of the mainspring. Instead of directly receiving power from the mainspring, a constant force mechanism stores and releases a precisely uniform amount of energy to the balance wheel at each oscillation. This ensures that the balance wheel's amplitude remains stable, leading to a consistent rate and superior chronometric performance throughout the watch's power reserve. It is a complex challenge, representing one of the highest achievements in mechanical watchmaking, and only a handful of brands have successfully tackled it.
A Revolutionary Escapement: The Silicon “Butterfly”
Among the most innovative solutions to the constant force dilemma is the one developed by Girard-Perregaux. Their Neo Constant Escapement, specifically reference 93510-52-3552-5CX, showcases a truly revolutionary approach. At its heart is a flexible silicon blade that acts as the escapement spring. This wafer-thin component, measuring just 14 microns wide and 120 microns thick—six times thinner than a human hair—is designed to store and release energy in a steady, controlled impulse to the balance wheel. The very idea for this blade is said to have originated from a Girard-Perregaux watchmaker observing a train ticket as it curved into a C shape before abruptly snapping into the opposite arc, a phenomenon known as buckling. This observation led to the conceptualization of a spring in the regulating organ that could harness this buckling principle.
The development of such a delicate and precise silicon component was made possible through collaboration with Sigatec during the 1990s, particularly with the advent of Deep Reactive Ion Etching (DRIE) technology. This advanced manufacturing process allowed for the creation of intricate silicon structures with unprecedented accuracy. The efficacy of this technology was recognized when the Constant Escapement L.M. watch, which debuted in 2013 and featured this innovative system, was awarded the prestigious Aiguille d’Or at the Grand Prix d’Horlogerie de Genève (GPHG).
The GP09200 Movement: Engineering at its Zenith
The Girard-Perregaux Neo Constant Escapement is powered by the in-house, manual-winding GP09200 caliber, a movement that is the culmination of 20 years of dedicated research and development, resulting in 15 patents, with two additional patents pending. This chronometer-certified movement operates at a frequency of 3Hz, or 21,600 vibrations per hour.
The intricate mechanics of the GP09200 are a testament to high horology. The movement incorporates a "fifth wheel" linked to the gear train, which channels energy to two escape wheels. Each of these escape wheels is equipped with three teeth and works in harmony with the movement’s 3Hz frequency. Energy is delivered alternately, rather than simultaneously, through a rocking lever to the buckling silicon blade. This silicon blade spring is wound with each oscillation of the balance, a process that occurs six times per second. The result is a mesmerizing, pulsating movement of the purple blade, often likened to a butterfly flapping its wings. This deliberate interruption in power flow between the twin barrels and the escapement ensures that the force serving the balance wheel remains uniform until the mainspring is fully unwound, guaranteeing a consistent amplitude and a constant rate throughout its impressive seven-day power reserve. The chronometric success of the movement is further ensured by rigorous testing, with dozens of silicon escapement springs evaluated to achieve the perfect geometry before COSC certification.
Architectural Grandeur: Design and Aesthetics
The technical brilliance of the Neo Constant Escapement is matched by its striking aesthetic presentation. The watch is housed in an 18K pink gold case, measuring a substantial 45mm in diameter and 14.8mm in thickness, featuring a combination of brushed and polished finishes. Its openworked design immediately draws the eye to the symmetric elements of the movement, prominently displayed on the dial side. The characteristic golden bridges at 6 o’clock are an unmistakable Girard-Perregaux trademark, symbolizing the brand’s rich heritage in haute horology.
Further enhancing its visual appeal is a linear power reserve indicator positioned at 9 o’clock, providing a clear and intuitive display of the remaining energy. The newly designed skeletonized hour and minute hands, crafted from pink gold, are enhanced with blue-glowing black luminescent material, ensuring optimal readability in various conditions. The watch also features a subtly reworked flange and indexes. The overall aesthetic is one of technical luxury, achieved through the sophisticated interplay of contrasting anthracite and pink gold tones, all crowned by a golden Girard-Perregaux logo that stands out against the intricate backdrop. The watch is completed with a black rubber strap featuring a fabric effect, secured by an 18K pink gold butterfly clasp, and offers a water resistance of 3 atm. This timepiece is not merely a time-telling instrument but a showcase of horological innovation and design.
The Pinnacle of Horological Innovation
The Girard-Perregaux Neo Constant Escapement stands as a significant achievement in the world of high horology. It represents a relentless pursuit of chronometric precision, combining cutting-edge materials like silicon with ingenious mechanical design principles. The watch is a testament to Girard-Perregaux's dedication to pushing the boundaries of traditional watchmaking, offering a unique blend of technical mastery and distinctive aesthetic appeal. It is a piece that invites admiration and study, embodying the spirit of innovation that continues to define the finest watchmaking houses.
Written by the Man of the Hour Editorial Team.