TAG Heuer Calibre 1887 McLaren 1974 Edition (CAR2A12.FT6033)

WORLDTEMPUS - 8 February 2012

It is entirely possible that the most precise mechanical watches of the future will no longer emit the mystically soothing tick-tock, but rather a soft hum. With a new escapement concept based on the physics principle of resonance, De Bethune effectively revolutionizes the idea of mechanical regulation in place since Christiaan Huygens, who lived from 1629 to 1695.
Certainly, resonance is not new in horology. The Bulova Accutron Spaceview launched in 1968, for example, utilized the principle of creating a magnetic field with its tuning fork caliber, which was a landmark in the history of timekeeping. However, this watch only functioned by the grace of a battery as its power supply; De Bethune has now achieved transferring the principle to a purely mechanical caliber.

In a "resonant" escapement, the components mesh in a controlled manner just like in a traditional mechanical oscillating system. In De Bethune's Resonique, the usual ensemble is replaced by two elements: a small wheel connected to the spring barrel (the magnetic rotor) and an oscillator shaped like a round frame surrounding the rotor. Oscillation is accomplished by magnetic resistance, in which the oscillator "opposes" the rotation of the rotor. This manner of controlling the flux of energy has never been seen in traditional escapements. In effect, the motion of the balance wheel is replaced by this invisible controlling energy. Shocks, stops, and restarts, which are as much sources of energy loss as of wear and tear, are also eliminated.
Above all, the Resonique permits endless frequencies of oscillation, thus very fine chronometric precision. For example, the latest edition of the Resonique escapement De Bethune successfully tested achieved a frequency of 925 Hz, which translates into 6.66 million vph!
Magnetic blades
Resonanace is a physics principle that sees a body vibrating with regularity while effectively transferring the vibrations to a second element - in this case, the rotor . The particularity of the Resonique - a term invented by De Bethune for the company's application of resonance in horology - is that there exists no physical contact between the rotor and the oscillator and that it combines mechanics and resonance, two sister sciences. The direction? of the vibrations can be "trained," which allows the magnets of the oscillator to remain in sync with the "magnetic blades" of the rotor.
This system differs from that of the Pendulum, an experimental escapement presented by TAG Heuer in 2010. In TAG Heuer's case, the balance spring is replaced by magnets functioning like a magnetic pendulum. Its architecture is effectively that of a Swiss lever escapement while the De Bethune Resonique works on a linear level. "It is as if the energy were a sprinter on a 400-meter track," says Denis Flageollet, watchmaker-concepteur and co-founder of the brand. "In the case of the Swiss lever escapement, you have to imagine it like a closed room that you need to cross back and forth all the time until you have gone the entire distance. With our escapement, this course is a straight line because there is no interruption."

Changing the paradigm
This new concept permits the significant elevation of a caliber's frequency. "In 2006, we presented an experimental escapement based on the swiss-lever architecture at Baselworld that attained 72,000 vph - 10 Hertz," the watchmaker recalls. " we were certain that in order to make it faster, we would need to find a radically different system." According to Flageollet, these speeds generate very important problems regarding the stability of the mechanism, its maintenance, and energy consumption.
An escapement functioning according to the principle of resonance - which is only theory at this point time - can attain a frequency up to 10,000 Hz, which is able to measure 1/10,0000th of a second, and this for many hours at a time. To succeed, Flageollet and his team have put in lots of effort regarding the crucial question of energy: the vibration of the oscillator to bring the oscillator to its frequency consumes enormous amounts of energy and the research of Siddarta Berns, De Bethune's physicist, who participated in the creation of the Resonique, essentially concerns this topic. Having once attained a vibratory state, energy consumption bly diminishes and stabilizes at a low amplitude of the oscillator .
"To master energy consumption, we need to be careful to reduce the oscillator to its minimum amplitude, the biggest source of loss," Flageollet continues. "The use of magnets mounted on a fixed, flexible frame permitted us to attain these high frequencies with minimal amplitude."
Beside this reduced energy consumption, the same architecture of the mechanism ensures a regular diffusion of energy. In effect, a drop in energy stops the vibratory state and residual energy continues to work in the spring barrel until it is completely empty.
"The magnetic field is concentrated in a small zone as it is difficult to influence," Flageollet concludes. "It is necessary to isolate the ensemble through a protection chamber made of mu-metal, an alloy of iron, nickel and molybdenum, which is known to deflect magnetic fields."

Stages of synchronization
From now on, all research will be concentrated on discovering the "stages of synchronization." These stages perfectly ensure vibratory frequency between the different elements and strive to find the path toward increasing frequency. De Bethune has chosen to make its discovery completely public and not protect it with a patent, inviting any and all researchers who hope to participate in this common journey of the watch universe to blog about it online at www.debethune-resonique.com.
Flageollet hopes this platform will aid in imagining future solutions for timekeeping.
Regulating sonneries
The Resonique opens totally new perspectives, even some not uniquely pertaining to the domain of precision chronometry. The morphology of the system is already illustrated by its small size and extreme finesse in comparison to normal escapements. Regardless, miniaturization is still possible. "Outside of regulation uses, this escapement could even be able to replace the gears in repeating calibers," Flageollet adds.
The shape of the rotor and the oscillator and their positions in relation to each other - rotor inside the oscillator in this case - can vary. Potential also exists with using other materials. "In order to reduce the size of the elements, it is conceivable, for example, to manufacture the oscillator in another nickel alloy as we did in our other attempts. It would also be realistic to try to realize a magnetic treatment in silicon or synthetic diamond."

VIEW THE DE BETHUNE ReSONIQUE FILM