Chronograph Saga 1 – Roots and Features
The chronograph is one of the most demanding complications to conceive and develop in watchmaking. Louis Moinet, also an astronomer, invented the chronograph for scientific purposes in 1816. He needed a highly precise instrument to measure the movement of the stars in the sky. He called his creation the “compteur de tierces,” in English “counter of thirds.” It was the first timing machine able to measure periods of time on demand. This masterpiece surprisingly appeared at auction in 2012 and was bought by the current eponymous brand. Its technical mastery astonished the watch community: indeed, this pocket counter can measure time to a precision of 1/60th of a second. This implies a movement frequency of 30 Hertz, a record-setter as the only other early chronograph this precise appeared one full century later: the Mikrograph invented by Charles-Auguste Heuer.
The word “chronograph” was coined with the next machine invented to measure periods of time on demand. In 1822, French horologist Nicolas Rieussec patented a machine that literally wrote its measurements. The system contained two horizontal discs, one for the minutes, the other for the seconds. Thanks to two ink dispensers, measurements were recorded by a drop of ink falling on each disc at the beginning and the end of the measurement. It was the Royal Academy of Science, who christened Rieussec’s invention “chronograph” by combining the Greek words chronos (“time”) and graphein (“to write”). The word has remained in use since then.
The chronograph is one of the most complex functions in mechanical watchmaking, even if that is somehow hard to believe considering how widespread a complication it is. The chronograph is actually the only high complication to attain such great success, though it shouldn’t come as such a surprise: decades ago, demand for it was high to time races, processes, medicinal measures, etc. For this reason, engineers have industrialized its production.
Today, the chronograph is far and away the most popular complication. Men in particular like the feeling of having a complex instrument with various counters and displays on the wrist. Some models have also become real icons in the world of watchmaking, sought-after by aficionados. These include the Daytona by Rolex, Omega’s Speedmaster, and the Navitimer by Breitling.
In this first episode of five comprising this “saga,” we introduce you to this underestimated horological complication.
http://www.thewatches.tv/en/editorial/c ... -features/
Chronograph Saga 2 – How It Works
In our last report we introduced the chronograph. Now, let’s have a look at how it works. The first point concerns controlling the functions. To to do, watchmakers invented pushers to start, stop, and reset the chronograph, and also to control the additional features on more complex versions like the split-seconds chronograph. In essence, the pushers are the exterior components of a whole system of commands, which makes them crucial as they govern the link between the pushers and the functions. The operating system can be imagined as the brain of the chronograph: the simplest ones use cams, which are parts designed to transmit and adapt information. The column wheel system constitutes a complex version of the chronograph’s operating system.
The chronograph is one of the two most complex complications that work on demand (as opposed to continuously like others such as the date do). Like the other on-demand complication – the minute repeater, which rings the time – the chronograph must be started and stopped. In a technical sense, this means that all the components belonging to the function are inactive by default. They begin working once the function is connected to the main movement that delivers the energy. This happens when the user pushes the start/stop button. At this moment, a connection between those two entities is made thanks to what is called a clutch. Throughout time, watchmakers developed two main kinds of clutches to activate the chronograph. The horizontal clutch is characterized by a wheel moving laterally to make contact with another wheel that belongs to the movement. The second one is the vertical clutch. Here, all the components are positioned on the same axis, including a disc controlled by a circular spring. The concept of the vertical clutch is thus different from the clear on/off system of the horizontal clutch. Indeed, the vertical clutch is always active, though the function only starts when the disc is pushed against the wheel of the chronograph. At this moment, it is released by a control system and the spring maintains the pressure against the chronograph wheel. To stop it, the control system pushes back the disc that continues to turn as it becomes part of the main movement.
The precision of a chronograph depends on various factors, but above all it depends on the movement, where the frequency of the caliber has a strong impact. The higher it is, the most precise the measure will be. For this reason the El Primero chronograph from Zenith is a reference on the market. It is the only one that is available at a larger scale with a precision of one-tenthof a second to beat at 5Hz. Usually, the frequency of a chronograph ranges between 3 and 4Hz. But in the end, the most unstable and unpredictable factor is the human itself. It takes 0.3 second for a man to react and press a chronograph’s pusher.
http://www.thewatches.tv/en/editorial/c ... -it-works/
Chronograph Saga 3 – The Flyback
The flyback chronograph is an evolution of the original complication. It allows the watch to restart a time measurement without having to first stop and reset the function. Indeed, the reset button of the flyback immediately restarts the timing function by automatically stopping, resetting, and starting the timing with just one push.
Before digital instruments became the norm, this function was of great help for pilots and their navigation needs as it helped them calculate distances and speeds with the immediate return-to-zero function without losing any time resetting the chronograph.
It’s perhaps not surprising that a brand long known for its pilot's watches, Longines, was the first to patent the flyback in 1936. Longines is a pioneer in watches for pilots, particularly with its two models the Weems and the Lindbergh, which integrate navigational tools into the dial.
The flyback chronograph has become ever more popular over the years, offering additional functionality to the regular chronograph without being as complex (and expensive) as the split-seconds chronograph we will cover in the next report.
The flyback chronograph can perhaps be described like the gentleman of the chronographs. It's not as aristocratic as the split-seconds chrono nor is it as casual as the standard chronograph.
http://www.thewatches.tv/en/editorial/c ... e-flyback/
Chronograph Saga 4 – The Split Seconds
The split-seconds chronograph is the most challenging version of the chronograph to create and manufacture. The usual chronographs display the totalization of seconds, minutes, and sometimes hours. But a chronograph can be improved to provide even more indications or functionalities. The flyback chronograph presented in the last episode was a first example. But the shining star of the category is undoubtedly the split-seconds chronograph.
Invented in 1831 by Austrian watchmaker Joseph-Thaddeus Winnerl, the split-seconds chronograph allows one to measure intermediate times within a time measure. In other words, instead of having to stop, reset, and start the function again you can simply display a first time with the timing measurement remaining active before coming back to it. This is possible by having two second hands, one stacked upon the other, and a pusher dedicated to the function. The hand on top can be considered the “leader.” In other words, this hand behaves like any usual chronograph second hand and comes back to its initial place only when the system is stopped. The other hand, which could be called the “follower,” is positioned underneath the first one and rides around with it by default. It enters into action only to obtain intermediate times.
The split-seconds chronograph is very demanding for watchmakers because of its complexity. It involves an additional system within the function that is really delicate to set. In fact, few brands are able to manufacture split-seconds chronographs because of this. As is often the case in watchmaking, some geniuses pushed the boundaries even further by adding more second hands to measure more intervals. But these pieces are exceptions.
http://www.thewatches.tv/en/editorial/c ... t-seconds/
Chronograph Saga 5 – Very Special Chronographs
Some chronographs broke the rules by bringing innovation and novelty to the chronograph at the same time. We selected five of the most relevant examples to focus on.
The first one is no longer for sale even if it is a recent introduction and a highly innovative one. Developed by Guy Sémon, current managing director and also head of research and development at TAG Heuer, the Mikrogirder put super high speed into a chronograph for much higher precision. Usually, the frequency of a chronograph is 21,600 or 28,800 beats per hour, also measured as 3 or 4 Hertz. These frequencies correspond to a precision of one-third or one-fourth of a second. The frequency of the Mikrogirder is 1/2000th of a second, or in other words 7,200,000 beats per hour (1000 Hertz). It remains today the fastest chronograph on the market – if you can still find one.
The second example is the Audemars Piguet Royal Oak Concept Laptimer Michael Schumacher chronograph. Launched in the spring of 2015, this new chronograph is a smart, innovative, and simultaneously traditional machine. It has two second hands positioned one on top of the other, which aid in displaying various lap times.
But what is really cool with the Laptimer is that it can be used in various situations, even the simplest ones. It is first and foremost a regular chronograph with a start, stop, and reset function. Then this chronograph also works as a regular flyback chronograph. But it can provide more information than that.
The laptimer function has its own pusher at 9 o’clock, which allows one to play with the two second hands to record lap times in various ways. Measuring a lap starts as usual by pressing the start pusher and the two hands move together. By pressing the laptimer pusher, the first hand stops and the second one automatically flies back to 12 o’clock and starts a new measure. By pressing again, the second hand stops and the first one comes back and starts running. And this can be repeated again and again.
But the Royal Oak Concept Laptimer Michael Schumacher also allows one to restart the moving hand by pressing the reset pusher. You may want to do this if you want to save the previous measure and not take the current one into account. At the end of the measure, the stop button gathers the two hands and the reset them to 12 o’clock. The engineering team of Audemars Piguet Renaud et Papi, who conceived the Royal Oak Concept Laptimer Michael Schumacher’s Caliber 2923, introduced three column wheels and a new kind of oscillating pinion to the movement.
The next chronograph we focus on comes from the famous Vallée de Joux. In 2007, Jaeger-LeCoultre introduced its Dual Wing concept within the Duomètre à Chronograph. The Dual Wing system comprises a new kind of movement architecture. To improve chronometry, the watch’s additional functions have their own source of energy, spring barrel, and gear train. They only share the regulating system with the main movement. This also architecture opens new ways of displaying the functions, and the Duomètre à Chronographe is a good example. Indeed, the function (chronograph) is located on the right side of the movement, clearly distinct from the main movement thanks to a different color used for the hands. This helps the legibility of the chronograph function, which is controlled by a single pusher.
Finally, De Bethune also introduced an interesting chronograph in 2014: the DB29 MaxiChrono. Its main feature is that all the hands are coaxially mounted in the middle of the dial. To achieve this, the brand developed a system in which each of the chronograph functions has its own dedicated clutch to minimize wear and maximize reliability. One of these clutches is particularly interesting because it looks like a vertical or column wheel clutch, but works like a horizontal or lever clutch.
http://www.thewatches.tv/en/editorial/c ... onographs/
Statistics: Posted by koimaster — Today, 9:05am