Parmigiani Fleurier Bugatti Type 370

The passion nurtured by Parmigiani Fleurier for mechanical challenges has given rise to a revolutionary watchmaking conception. Inspired by automobile technology, the Bugatti model with transveral movement by Parmigiani Fleurier asserts its exceptional aesthetics by arranging its constituent parts like an engine block on the wrist, along a horizontal rather than a vertical axis. The art of watchmaking meets the automobile world.

For the first time, the Bugatti Type 370 wristwatch incorporates a movement spread between five plates, held by cross-arms. As if in a cross-section, their well-spaced alignment enables one to observe the movement in operation, with its gears and its extraordinarily elaborate technical features. The visual accessibility at the heart of the movement is entirely original and truly unique, to a degree that could previously only be reached in the virtual world. The concept of the Bugatti Type 370 rises to this new challenge and opens up a whole new dimension.

A peerless centre of competences equipped with comprehensive and entirely independent industrial facilities makes it possible to guarantee the unique and exclusive character of the Parmigiani Fleurier brand. This asset confirms its technical and creative capacities, which are now symbolised, alongside other innovations, by the Bugatti Type 370 watch. All components and plates were developed, machined, decorated, assembled and then cased up in the workshops of the Manufacture Parmigiani Fleurier.

The disc declutching and tube spring
Generally speaking, the time-setting friction makes it possible to index the hands on the dial. This function is usually performed by the hour-wheel or the cannon-pinion, simply by gripping along an axis.In the case of the Bugatti type 370, it is a tube spring mechanism that presses on a disc (disc declutching) to enable time-setting along a complex axis that is extremely hard to achieve.

The cardans
Under the transversal movement, the cardans serve to make the connection between the external function (time-setting or winding) and the interior function. Since the movement of the Bugatti Type 370 is mounted on “silent blocks”, there cannot be any fixed axis. The cardans avoid a rigid connection between the movement and the case exterior.

The pinions with cone-shaped toothing
The 2 pinions with cone-shaped toothing serve as an intermediate device for the energy transmitted to the crown to travel from the axis of the winding or time-setting crown through to the perpendicular axis of the movement. Cone-shaped toothing is extremely rare in watchmaking, calling for sophisticated techniques and custom-made tools in order to cut them properly. This complex finish enables 90% effective gearing (due to a better spread of the point of contact) and a more efficient intermediate energy transmission function.

The cone-shaped differential
To ensure the smooth operation of the power-reserve, a differential was developed by the micro-mechanical engineers in order to link the toothing of the barrel and its ratchet. To optimise the differential gearing with its satellite, the definition of the tooth had to be enhanced, which in turn called for new machining procedures, entirely developed within the Manufacture Parmigiani Fleurier, as indeed are all components of the Bugatti Type 370 watch.

Drum power-reserve
The visibility of the movement, thanks to its skilfully aligned plates, provides infinite scope for playing with the aesthetics of its components. In harmony with the transversal nature of the movement and in order to identify its power-reserve, Parmigiani Fleurier made it accessible by means of a read-off on a drum. So as to optimise the constancy of torque for the 10-day power-reserve, a series-coupled twin barrel is used.

Wheels shaped like car wheel rims
In celebration of the automobile spirit, while remaining faithful to its quest for extreme refinement, Parmigiani Fleurier has devoted meticulous attention to each detail of the movement. For the first time, movement wheels have been designed to reflect the aesthetic appearance of a wheel rim and thus remain in tune with the original concept. Inspired by the famous double wheel-rim invented by Ettore Bugatti in the 1930s, the two dedicated wheels in the movement feature arms cut according to the same design.

The micro-bolts
To add the perfect finishing touch to the aesthetic appeal of the movement, Parmigiani Fleurier has replaced the screws by micro-bolts used to assemble the engine block.

The exclusive design of the Bugatti Type 370 watch
Right from its conception, the original idea by Michel Parmigiani – “ an engine block on the wrist which also happens to tell the time” – was enthusiastically received by the famous automobile company. This concept gave rise to an elaborate exterior designed to highlight the beauty of its revolutionary mechanism, never yet created within a wristwatch. Crafted in 18-carat white gold, its case makes observing the movement both accessible and entertaining thanks to the six sapphire crystals, often cambered and domed to the extreme.

Created in eight parts, its conception is extremely complex, calling for a large number of sophisticated sets of tools, custom-machined and never yet seen in watchmaking. In order to protect its transversal movement and to guarantee optimal shock-absorption, the workshops of the Manufacture Parmigiani Fleurier specialising in watch exteriors developed a system comparable to the chassis of an automobile: the movement is thus placed on “silent blocks”. Water-resistant to 3 atmospheres, the Bugatti Type 370 uses 3-dimensional joint planes.

The silent blocks
The structure of the movement, arranged on five plates is held to the case by four silent blocks which absorb vibrations and preserve the cone-shaped gearing (for time setting and winding) from external stresses and strains. Directly inspired by automobile construction, its “shock absorbers” are a first in the world of Haute Horlogerie.

The glasses
The various openings on the case are accessible thanks to six sapphire crystals specially shaped to match each “porthole”. Their conception required months of study and technologies that did not even exist a few years ago. The magnifying glass protecting the dial features a toric form of cambering (along two different axes) that is extremely complex to achieve. The sides of the cases feature extremely elongated banana-shaped glasses. The “hood” of the movement consists of a strongly inward curving sapphire crystal. The glass on the case-back at behind the movement are also crafted in sapphire.

The eight parts of the case
The difficulty in crafting the Bugatti Type 370 case is far greater than for traditional production of a wristwatch. Its eight-part design, consisting of six soldered parts and two attachments, represents an imposing technical challenge. All components, entirely machined at the heart of the Manufacture Parmigiani Fleurier, are assembled, before soldering, on a slab of marble where everything is lined up. This benchmark for basic levelness in order to establish the points of reference is also inspired by the world of car manufacturing. Several hours are required to position and solder the parts of the case in order to ensure they are not distorted. Gold retains the memory of its initial structure and the process of stabilising its shape calls for an exceptional level of knowledge.

The “choke”: a world first
The time-setting and winding of the movement are totally revolutionary. A “choke”, in the shape of an instrument external to the watch, is used to action the two crowns placed beneath the case. Its complex dynamometric system, which may be disconnected at any moment, makes it possible to deliver constant force to the cardan winding-stem. Time-setting (by disc clutching with tube spring) is done by means of manual rotations performed with the other end of the “choke”. Development of the “choke” called for over three years of research and represents a world première.

The system of this mechanical instrument is composed of five levels of functions, from winding the “choke” to releasing the energy in the crown.Located at the head of the instrument, the first level is composed of a gear serving to reduce the revolutions performed by the hook of the starter. Usually, three or four turns are enough to store a large quantity of energy which is then released in the crown. This device is coupled with an anti-return of force system.

The second level is made up of a set of two parallel barrels, with springs that tauten once the energy is stored. A declutching system ensurea maximum control of torque.The third level is again composed of a gear linked to two barrels.A speed regulating system plays its role at the fourth level of the “choke”, thanks to a chamber filled with liquid silicon in which a blade fixed to the arbor turns steadily.

The last level enables the activation and the release of the “choke”. Its central axis is composed of a friction cone held by a spring. As soon as pressure is exercised, the cone frees itself and thereby releases the torque. Once the pressure slackens, the mechanism stops. If any resistance is met when pressing the crown, a specially designed safety declutching mechanism goes into action.