Carl F. Bucherer Automatic CFB A1000 Caliber

CFB A1000, the first in-house automatic watch movement by Carl F. Bucherer, was unveiled at Baselworld 2008.

The origins of this movement go all the way back to the year 2005. For it was then that a basic decision was taken to add a new facet to the multifarious Carl F. Bucherer watch collection that would demand an extremely high level of technical expertise and craftsmanship. Putting the company’s philosophy into practice on a broad scale literally meant it had to create its own watch movements.

And it took three years to develop the first caliber manufactured in-house and bearing the signature of Carl F. Bucherer. From the very start, the company expressly ruled out the idea of ‘cloning’: in other words, copying an existing movement that was no longer protected by patent. And it soon decided to go ahead with a revolutionary new automatic movement with unique design features.

The list of specifications also included a range of different targets, such as:-
– The use of conventional, tried-and-tested technologies such as a classic regulatory system, a Swiss club-tooth lever escapement, and a traditional going train with jeweled bearings
– A progressive caliber design with an unimpeded view of the bridges, bars and other components
– A platform principle, which would facilitate the addition of new features to the movement as required
– High reliability
– Semi-industrial production of the movement blanks

The new CFB A1000 automatic caliber fulfils all these requirements without exception. Apart from this, the technicians and watchmakers at Carl F. Bucherer have added a whole string of unusual and unconventional features.

Peripheral Winding Rotor
One of the first questions that arose when designing the automatic caliber was where to place the rotor. Looking back through the history of watchmaking, it seemed there were four distinct possibilities:-
1. To mount it centrally, this means that the rotor moves over the entire surface of the movement. This design, which has proven itself time and time again, has the disadvantage that it always partially obscures our view of the movement.
2. To mount it eccentrically, above the movement. Here we face the same problems as with the central rotor.
3. To integrate a micro rotor into the movement itself. This system conceals nothing but because of its design calls for smaller components.
4. To have the rotor revolving around the edge of the movement. In view of the exacting demands on its design, this type of rotor arrangement is the most infrequently found of the four possibilities. It combines the technical advantages of the centrally mounted rotor with the optical virtues of the micro rotor.

With the CFB A1000 caliber, Carl F. Bucherer consciously chose the fourth variety, fully aware of the fact that many of its features would have to be redesigned from the bottom up. Unlike earlier versions of this design, the peripherally positioned rotor – which has been registered for patent – has an efficient shock-absorption system. The rotor bearing is built to withstand even the most exacting conditions. It is assisted by DLC-coated rollers, which, in their turn, are equipped with ball bearings, which are made of ceramic; make the system virtually maintenance-free. The abbreviation DLC stands for diamond like carbon, which is an extremely hard and resistant carbon coating.

This process has been reliably used in the manufacture of surgical instruments for some time now. Apart from this, it helps to increase the useful life of industrially produced tools such as drills or milling equipment. DLC is considerably harder and more resilient than more commonly found PVD coatings, and adheres particularly well to stainless steel. The thickness of the coating, which can be applied at a maximum of 250 °C, is around one thousandth of a milimeter. Its hardness is 2000 Vickers, or about three times that of steel.

Dynamic Shock Absorption (DSA)
In the CFB A1000 caliber, the roller/ball bearing units are mounted on rocking bars, which are precisely positioned by springs. The setting of these rocking bars takes place through a cam. The new dynamic shock absorption (DSA) system is highly efficient. A transmission wheel transfers the rotor’s kinetic energy to the winding mechanism.

Carl F. Bucherer has equipped this transmission wheel with two Incabloc shock-absorption systems to ensure that its axis does not snap in the event of a sharp impact. In such a case – by no means unusual for a wristwatch – the walls of the bridge limit the radial displacement of the rotor. Any axial play is held in check by special screws. This prevents the rotor from banging against the bottom of the case.

Bidirectional Winding
Another of the new automatic movement’s outstanding features is the efficiency of the self-winding mechanism. The rotor supplies energy when turning in either direction. The rotor’s movements are polarized by a low-loss winding system. It consists of two clutch wheels with eccentrically mounted clamp rollers. The pair of wheels spring into action reciprocally and are not only simple in design but also very reliable. They require no lubricant and are likewise maintenance-free.

Central Dual Adjusting System (CDAS)
The heart and soul of any mechanical watch is its balance and spring in combination with the escapement. And here, too, Carl F. Bucherer has come up with another patented innovation. In this case it is CDAS, which stands for Central Dual Adjusting System.

The main advantages of the intelligent precision adjustment system with its central control element are:-
– The balance and escapement require adjustment only once. The system is subsequently secured in position to protect it against shocks.
– To guarantee the system’s long-term quality, precision adjustment can only be carried out using a special key issued exclusively to authorized service centers.
The balance and stem are bearing-mounted at both ends by two identical Incabloc shock absorption systems, which permits optimum setting of the endshake.

The design and decoration of the 30-millimeter wide and 4.3-millimeter high movement are an expression both of the high-quality technology and the brand philosophy of Carl F. Bucherer. The bridges and bars situated at various levels are exquisitely finished, featuring matt and brushed surfaces with diamond-cut facets. Alternating matt, brushed and polished surfaces ensure the high optical quality of many of the other components. But the main function of any watch movement is to measure and display the time. The CFB A1000 caliber shows the hours and minutes on centrally positioned hands. For the seconds, there is a small hand at 6 o’clock. Needless to say, Carl F. Bucherer will be adding a number of useful functions to the basic movement. These may include a large date, a day display or even a power reserve indicator.

Technical details
CFB A1000 caliber: Mechanical automatic movement wound by a bidirectional rotor running around its edge.
– Diameter: 13˝ or 30 mm
– Height: 4.30 mm
– Functional jewels: 29
– Frequency: 21,600 beats per hour/3 Hz
– Power reserve: approx. 55 hours
– Escapement: Swiss club-tooth lever escapement
– Subassembly: Nivarox Type ASUAG No. 8
– Balance: ring-shaped, gold-plated Glucydur beryllium alloy balance
– Double roller: nickel-plated brass
– Impulse pin: jewel, red
– Balance spring: flat (volute), CGS 71, Anachron, thermally treated ‘Etastable’
– Collet: Greiner
– Escape wheel: steel, polished flat, 1 chamfer, polished impulse face, epilame-coated
– Pallet: steel, polished flat, fork notch rounded off
– Pallet stones: red, synthetic ruby, epilame-coated
– Impulse angle: 50°
– Index: classical

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