After being invited to give a talk to the Swiss Chronometry Society (SSC), Xavier Rousset will also be paying a visit to EPHJ. In news that is sure to get movement designers very excited, it seems that escapements still offer scope for innovation in 2023!
By Joël A. Grandjean / JSH Magazine
Mechanical watch movements are miraculous things! How they can fit so many components into such a small space is beyond comprehension. Even so, the holy grail for those who design them would be to have more space…
The birth of the ‘Jura lever’?
“In this new system, the rotation axle of the oscillator coincides with that of the escape wheel, and the pallet with its fork and guard pin is on the same side as the arms holding the entrance and exit pallets,” explains microtechnology engineer Xavier Rousset. Bear in mind that in a wristwatch, the mechanical oscillator is generally a balance and spring assembly and the regulating organ a detached lever escapement. Meanwhile, the escape wheel pivots along an axle parallel to the axle of the oscillator, meaning that the centre-to-centre distances between the two organs and the lever are often the same.
The Mono’Axe is patented and has achieved the highest technology readiness level (TRL) in the TRL scale (see box). “This innovation keeps the oscillator-escapement system working and maintains its performance while reducing its overall volume,” adds the designer, who, given where it saw the light of day, would love to name the invention the ‘Jura lever’.
30% more compact!
This will surely be a spur to manufacturers’ creativity. Just imagine what could now be added in the freed-up space, in terms of technical improvements and sophistication. While the new system somewhat enhances the performance of the power reserve (as demonstrated by a comparative test carried out between the unchanged SE-100 (Schwarz Etienne) movement and the Mono’Axe prototype), more than any chronometric gains it is primarily the space savings that are likely to fire the imagination of motor manufacturers…
Xavier Rousset, well known for showcasing the crafts with his XRby brand, is also a driving force behind the research and development of watchmaking systems. He brings together university and co-contracting ecosystems, mainly in Switzerland’s ‘Jura Arc’, to offer patent operating licences and studies assessed using the TRL scale: a system familiar to NASA and ESA that enables a project’s maturity to be rated vis-à-vis its actual feasibility.