Tourbillon
In horology, a tourbillion (/tʊərˈbɪljən/) or tourbillon (/tʊərbɪˈjɒn/; French: [tuʁbijɔ̃] "whirlwind") is an addition to the mechanics of a watch escapement to increase accuracy.
Patented by Breguet in 1801, the single axis tourbillon minimizes the difference in rate between positions caused by poise errors.
In 1980 Anthony Randall made a double-axis tourbillon in a carriage clock, which was located in the (now closed) Time Museum in Rockford, Illinois, US, and was included in their Catalogue of Chronometers.
[7] Prescher invented the constant-force mechanism to equalize the effects of a wound and unwound mainspring, friction, and gravitation.
In 2005, Greubel Forsey presented their Quadruple Tourbillon à Différentiel (QDT), using two double-tourbillons working independently.
It was presented at Baselworld 2004 in Basel, Switzerland, in a set of three watches including a single-axis, a double-axis and a triple-axis tourbillon.
The world's unique tri-axial tourbillon movement for wristwatch, with traditional jewel bearings only, was invented by the independent watchmaker Aaron Becsei, from Bexei Watches, in 2007.
[10] In the three axis tourbillon movement, the 3rd (external) cage has a unique form which provides the possibility of using jewel bearings everywhere, instead of ball-bearings.
Examples of companies and watchmakers that include this mechanism are Vianney Halter in his "Deep Space" watch, Thomas Prescher, Aaron Becsei, Girard-Perregaux with the "Tri-Axial Tourbillon", Purnell with the "Spherion",[12] and Jaeger LeCoultre with the "Heliotourbillon", released in 2024.
[16] High-quality tourbillon wristwatches, usually made by the Swiss luxury watch industry, are very expensive, and typically retail for tens of thousands of dollars or euros, with much higher prices in the hundreds of thousands of dollars or euros being common.
Sometimes termed, appropriately enough, the "open heart", these are sometimes misrepresented by unscrupulous dealers as a tourbillon (and "tourbillon-style" by ethical ones).
