While the chronograph is certainly one of the most popular complications, most people do not realize that it is among the most complex mechanisms to develop and assemble. While most chronographs are based on a timekeeping “engine”, on which a second gear train engages to drive the chronograph, some folks found this idea inefficient (and in a way, it is). Breguet, within the Tradition collection, has a chronograph that approaches things in a different way. Complex, visually antique, but in fact very modern, here’s our take on the Breguet Tradition Independent Chronograph 7077.
The challenges behind a traditional chronograph
Most traditional chronographs are built around a base mechanism driving the time indication and a chronograph mechanism that engages with this base movement when it is started – there are two gear trains (one for the time, one for the chronograph) that are linked by a clutch (vertical or horizontal). The chronograph is driven by the timekeeping mechanism – a common solution that poses several challenges. Among these, the amplitude of the balance wheel is adversely affected when the chronograph is engaged – the chronograph takes its energy from the base movement… Activating the chronograph means that the entire precision of the watch is affected, which you’ll admit is incompatible with the idea of a precision instrument.
Independent chronograph mechanism
Introduced at Baselworld 2015, the Breguet 7077 mechanism is built in a truly original and ingenious way, and the chronograph mechanism is completely independent and autonomous. There is no interaction between the timekeeping indication and the chronograph. On one side, an independent “sub-movement” – composed of one barrel, one gear train, and one oscillator – drives the indication of the time. On the other side, an independent mechanism, with its own energy source, gear train and oscillator, regulates the chronograph functions. As a consequence, there is no interference in energy consumption and the rate of the timekeeping movement remains unaffected when the chronograph is started.
On the right side is the going train for the time indication, which is regulated by a 3Hz oscillator and has a power reserve of 55 hours. On the left side is the chronograph part, which operates at a 5Hz frequency, for enhanced precision. Its balance wheel is fashioned out of lightweight titanium, allowing for perfect symmetry with its 3Hz counterpart. Both come with a silicon Breguet hairspring and silicon pallet escapements.
The energy source for the chronograph mechanism is not a spring coiled in a barrel. In the case of the Tradition Independent Chronograph 7077, Breguet uses a different type of spring. The energy is stored in a flexed blade spring that requires less space. The resulting power reserve for the chronograph mechanism is of 20 minutes, which is sufficient to time short periods of time. A smart and practical solution, this blade is flexed when resetting the chronograph. So you never need to care about winding the chronograph mechanism. Pressing the reset pusher flexes and arms the blade spring.
From a technical perspective, the chronograph mechanism is controlled by two brakes. Its titanium balance wheel is freed when the chronograph is started and blocked when it is stopped. A chronograph activation indicator is located at 6 o’clock.
Pure Breguet Styling
The Tradition Independent Chronograph 7077 is Breguet through and through. The style is symmetrical, on either side of the watch. The distinctive movement architecture is inspired by that of the Breguet subscription watches.
The 44mm case features welded straight lugs and a fluted caseband. The two chronograph pushers are screwed in. One pusher is used to start the chronograph, the other to stop and reset it. The watch is almost completely openworked with a hand-guilloché silvered gold dial offset at 12 o’clock. In the purest Breguet tradition, the hands are blued. The chronograph seconds hand is in the centre. Directly opposite each other, at 2 o’clock and 10 o’clock, two retrograde hands respectively indicate the power reserve of the watch and the chronograph minutes (20-minute counter).
As always with Breguet, the movement is perfectly crafted with a matte grey frosted finish. Its sophisticated three-dimensional architecture that mimics Breguet pocket watches is superb. The shock protection system for the balance wheels highlights one of Breguet’s inventions, the “Parechute” with its distinctive blade spring to hold the pivots.
The Breguet Tradition Independent Chronograph 7077 comes in white or pink gold. It is presented on an alligator strap secured with a folding buckle.
The Breguet Tradition Independent Chronograph 7077 feels timeless yet modern. It displays an assertive personality paired with remarkable technical sophistication. At CHF 77,000 in pink gold and CHF 77,800 in white gold, this original chronograph is not for every pocket but can be worn in confidence in front of the most rarefied gatherings of watch snobs. For more information, please visit www.breguet.com.