Ever since its founding in 2002, the spirit of independence cultivated by the Manufacture De Bethune has been driving its teams and is clearly apparent in terms of both the projects undertaken and the resulting achievements.This creative as well as technical freedom has enabled the R&D division to tackle research in the field of fundamental horology, particularly geared towards improving the regulating organ of mechanical watches.
The multi-disciplinary skills and the technical experience of its team have enabled it to open up a whole new chapter on the escapement and oscillators, by breaking free of existing escapements and sprung balances.
The development of its own balance wheels featuring high quality factors such as thermal self-compensation, an optimised weight/inertia ratio and a semi-rigid terminal curve, led to the integration of its innovations within various in-house calibres: different types of patented De Bethune balance wheels, a De Bethune balance spring with flat terminal curve; and a silicon escape wheel.
The brand thus began equipping its watches with several 28,800 vph calibres and three 36,000 movements in tourbillon, chronograph and tourbillon chronograph versions.
High frequency has been proven and acknowledged to be a significant factor for the mechanical movement of a wristwatch, because the higher the frequency of its calibre, the less it will be sensitive to the inevitable shocks sustained by a watch when worn on the wrist.
A number of tests were conducted with a view to increasing the frequency of the regulating organ. In 2006, De Bethune presented its first timepiece beating at a frequency of 72,000 vph (10 Hz), equipped with a silicon escapement and a self-compensating sprung balance.
This watch and its lab clones demonstrated that increasing the frequency of the sprung balance beyond 5 Hz necessarily implies risks and premature wear of components – results that were incompatible with De Bethune’s self-imposed standards of quality and reliability. Since the limits of the current system had been reached, it was clearly time to move on to a radical alternative solution making it possible to achieve 10 to 100 times higher frequencies yet without disturbing the smooth running of the movement or damaging its components.
This involved increasing the quality of the oscillator, the efficiency of the escapement, as well as working with low amplitudes in order to guarantee a power reserve sufficient to be applied to a wristwatch.
The field of research was therefore broadened and new paths were explored that quickly led to a new series of experiments and a number of tests.
As of 2007, De Bethune launched studies on various types of “oscillating” resonators and escapements in order to move beyond the maximum 5 Hz frequency critical threshold defined by the De Bethune technical laboratory. This field of research proved to be truly vast, given the diversity of the shapes and materials that can be made to resonate, as well as the boundless potential for inventing different types of escapement.
On December 8th 2011, De Bethune officially and publicly announced its research in the field of fundamental horology aimed at developing a new type of regulating organ named Résonique.
The concept and the innovative idea are not patented, given the vast scope of the research in a previously unexplored field. This choice tends to apply the so-called “open source” models based on transparency and information-sharing aimed at achieving enhanced productivity and typically used in IT, scientific, technological and even artistic fields, where the concept of intellectual property is rapidly evolving.
De Bethune wanted its work on Résonique to be shared and picked up by the watchmaking community in order to work together and jointly contribute to the significant development and fine-tuning of an alternative solution to the sprung balance system and the traditional lever escapement.
By way of reminder, an acoustic oscillator vibrating at a frequency of 928 Hz (6,681,600 vph) with a new magnetic-type escapement had been presented at the press conference on December 8th 2011.
Several articles, a blog and a presentation at the Société Suisse de Chronométrie (SSC) provided an account of De Bethune’s work on the operation of this prototype.
The evolution of our research in fundamental horology over the past two years leads us to the following observation:
The improvement of an oscillator’s performance depends both on its intrinsic properties and on the type of movement powering it. It was thus important to opt for a continuous movement rather than a back-and-forth system and to avoid a pivoting oscillator.
De Bethune focused on two particular issues:
=> testing various types of resonators with several degrees of freedom; and
=> creating an escapement designed to avoid the stopping and back-and-forth motion that disturb traditional lever escapements.
Films from the De Bethune technical laboratory show large-sized resonators adapted to various degree of freedom in operation and sustained by a freely rotating magnetic escapement.
Exclusive: This type of magnetic escapement leaves the resonator several cycles of free oscillations between each impulse phase.
De Bethune contributes on its own level to influencing and stimulating watchmaking development. Résonique, which represents a complete break with the traditional sprung balance, has generated a new process of reflection and paved the way for a number of developments, multi-partner research projects, patent registrations, and many other confidential studies. It is thus definitely by communicating and sharing knowledge that ideas are born and take shape.
The forthcoming developments from the technical laboratory will involve defining the chronometric (precision timing) properties of the various resonators with several degrees of freedom, as well as the development of a free magnetic escapement with secure synchronisation.
The www.resonique.com blog will soon be enhanced by some of our latest research and notably by some high-speed camera video recordings of the above-described oscillators and escapements.
The Watches TV visits De Bethune’s manufacture where Denis Flageollet, co-founder and Head of Technical Department, explains their new approach to the regulation of watches: A magnetic oscillating system opening the door to frequencies as high as 20’000 Hertz.
For more on The Watches TV, please visit http://www.thewatches.tv/en/watchthis/de-bethune-acoustic-oscillating-escapement/
