Press release
The spherical differential connecting the four rotating carriages of the Quadruple Tourbillon is a prime example of Greubel Forsey's inventive approach as it exhibits an unprecedented degree of complexity, refinement and timekeeping performance.
The four asynchronous tourbillons independently contribute to its extremely high accuracy.
The spherical differential acts like a car's differential in distributing torque between two wheels while allowing them to rotate at different speeds.
The two double-tourbillions are in an asymmetrical format to provide clear visibility to all carriages on the dial side, as well as providing an additional lateral view.
Patented movement
Movement dimensions
Diameter: 36.4 mm
Thickness: 9.70 mm
Number of parts
Complete movement: 531 parts
2 double Tourbillon cages: 128 parts each
Weight of each double cage: 1.17 g
Spherical differential: 28 parts
Number of jewels:63
Olived-domed jewels in gold chatons
Power reserve: 50 hours
Barrels: Rapid rotating twin barrels (1 Turn in 3.2 hours) one of which is equipped with a slipping spring
to avoid excess tension
Balance wheel: Free sprung balance with white gold mean-time screws (10.7 mm diameter)
Frequency: 21'600 vibrations/hour
Balance spring
Phillips terminal curve
Geneva-style stud
Main Plates: Nickel silver, spotted nickel palladium-finish, hand bevelled, straight-grained flanks, polished counter-sinks
Bridges
Barrel bridge:nickel silver, hand bevelled and frosted, nickel palladium-finish, “Greubel Forsey” gold plate
with the individual number of the timepiece
Two steel Tourbillon bridges (movement side): hand-bevelled, flat black polished with polished counter-sinks
Two sapphire Tourbillon bridges (dial side)
Gearing
Involute circle profile
Conical gearing with corrected profile
Inner Tourbillon
Inclined at a 30°angle, 1 rotation per minute
Outer Tourbillon
1 rotation in 4 minutes
Hand-bevelled and openworked cage pillars
Gold Greubel Forsey counterweights
Displays
Hours and minutes
Small second sector (mean performance)
Power reserve on a sector
Tourbillon rotation indicator (outer cage)in 240 seconds
Habillage
Case
Platinum with asymmetrical convex sapphire crystal
Transparent back with asymmetrical convex sapphire crystal
Lateral window with shaped sapphire crystal
3 dimensional, variable geometry-shaped lugs
Gold security screws
Case finishing
Polished bezel and centre band with hand-finished straight graining
Hand-engraved individual number
Raised engraving of the name of the Invention on a hand-punched background
Case dimensions
Diameter: 43.5 mm
Thickness: 16.06 mm
Water resistance of the case 3 atm – 30 m – 100 ft
Crown Platinum with engraved and black lacquered GF logo
Dial
Gold dial
Gold appliques
Gold display sectors
Applied gold logo
Hands
Hours and minutes, small seconds and power-reserve in gold
Strap Hand-sewn black alligator leather with gold folding clasp, hand-embossed with the Greubel Forsey initials
