The Tourbillon: Anti-Gravity for Watch Movements

Do you know what time it is? Chances are good that you used a computer or a cell phone to answer that question. The time on your phone is about as accurate as chronometry gets these days. That’s because cell networks are timed from satellites, which are in turn timed from atomic clocks. And these days, it may be that atomic clocks are the only clocks that matter.

Before this modern era of quartz and atomic accuracy, though, timepieces were mechanical. Clocks were driven by heavy weights that made them impractical for travel. It wasn’t until the mainspring-driven movement came along that timekeeping could even begin to become portable.

But while the invention of the mainspring made portable timepieces possible, it hurt their accuracy. That’s because the driving force of a tightly wound spring isn’t constant like that of an inert, solid weight.  So pocket watches weren’t exactly an overnight success. Early pieces were largely ornamental, and only told the hour. Worst of all, they would slow down throughout the day as the mainspring unwound, becoming useless unless wound several times a day. The mainspring wasn’t the only problem plaguing pocket watches, but it was the among the most obvious.

Time is a Balancing Act

Cutaway illustration of a pocket watch. Image via Wikipedia

Pocket watch accuracy was greatly improved when the balance spring came along. The balance spring acts like a pendulum does in a weight-driven clock to keep the gears moving at a metered pace.  Working in concert with the escapement, the balance spring governs the release of energy stored in the mainspring to the time wheels. Before the balance spring, energy from the mainspring was controlled only by the escapement. Even with the addition of balance springs, there was still a lot of room for improvement.

By nature, pocket watches spent much of their time in one of two positions: either stored upright in a waistcoat pocket, or lying flat in the hand or on a table. A famous Swiss-French watchmaker named Abraham-Louis Breguet believed that gravity and positional stagnancy affected his watch movements by causing them to run at varying speeds. In the late 1700s, he devised a solution: a kind of anti-gravity chamber that he called a tourbillon, a French word meaning ‘whirlwind’.

Caged Gymnastics

A single-axis tourbillon in motion. This gif shows two seconds of real-time motion and two seconds sped up. GIF via davisryan8

A tourbillon is known in horology (that’s the art and science of measuring time) as a type of complication. This term refers to anything a watch can do in addition to keeping the hours, minutes, and seconds. The simplest type of complication is a date keeper. The tourbillon is among the most complicated complications ever invented.

Breguet’s idea was to constantly rotate the elements of the watch movement at a controlled rate. This way, the positional errors would average out over time, essentially decreasing gravity’s effect on accuracy of the movement. To do this, Breguet mounted all the parts of the movement – that’s the escapement, balance wheel, and balance spring – in a cage, and rotated the cage at a rate of one revolution per minute.

Breguet’s tourbillon rotated the watch movement along a single axis. Though the tourbillon is debated now as to whether it was ever really useful, a single axis was all he needed keep the movement in motion against gravity. In the 1970s, someone made the first dual-axis tourbillon. Nowadays, there are three and even four-axis tourbillons being made here and there as the horological fascination continues.

Conspicuous Consumption

The watch in the banner is the Jaeger-LeCoultre Master Grande Tradition Gyrotourbillon 3 Jubilee watch, and you can watch it in motion below. You can see the balance spring quickly inhaling and exhaling inside the cage. This watch has a flying spherical tourbillon that moves in three axes, much like a gyroscope.

The flying tourbillon is called so because it is only supported from one side, rather than two. Flying tourbillons are a testament to the notion that modern tourbillons are complications for the sake of complication. The main purpose of using a single support is to make it easier to ogle the tourbillon’s action.

The tourbillon is revered in horology as an engineering marvel, and many modern watchmaking houses create them as a demonstration of their skills. They appear today in the most expensive wristwatches on Earth, although they serve no real purpose since wristwatches naturally change position all day long. Well-made but entry-level watches with genuine, hand-crafted tourbillons fetch at least $50,000. The really good ones start at about $250,000.

Although quartz movements and atomic timekeeping have made the tourbillon complication an expensive and nearly useless novelty, it remains an amazing piece of engineering to witness. Can’t afford a tourbillon watch? You could 3-D print a model of one like [Nicholas Manosous] did or make a tourbillon clock like [Christoph Lamier]. Here are some Thingiverse tourbillons to get you started.

Via r/EngineeringPorn

 

39 thoughts on “The Tourbillon: Anti-Gravity for Watch Movements

  1. I recently built a clock that uses a capacitor decaying to keep time. This had the same problem as the mainspring mechanical clocks: getting slower throughout the day. The solution is to discharge the capacitor through a constant current source, which is sort of the electrical equivalent of the balance springs. It’s elegant how the mechanical and electrical math is so similar.

    1. I guess if you think about it, capacitors ARE like electric springs.

      The amount of charge (Coulombs) stored in a capacitor is its capacitance times its voltage, and the amount of force (Newtons) exerted by a compressed spring is its spring constant times the distance it has been compressed.

      1. You can use Spice electric circuit simulators to solve mechanical systems. Why? because it’s the simplest software setup: get something like LTSpice or one of FOSS spice simulators (ngspice, etc) and they’ll insulate you from having to know details of numerical solvers, etc. , and there’s a lot of tutorials to get started.

    2. This is how McLaren discovered the “inerter” in Formula 1. There was a hole in the mechanical/ electrical symmetry, amd upon investigation, they developed a new kind of suspension damper (j-damper).

      I believe they are now used by every F1 manufacturer for their ability to control wheel recovery from jounce.

        1. Wikipedia claims interters are analogous to a capacitor. Which is interesting because I thought springs = capacitors… Now I need to know what the equivalent of an inductor is.

          1. I’ve got it, a flywheel = inductor. Stored energy depends on velocity and they cannot be stopped suddenly without a large force/voltage developing across them.

  2. I feel the following added in from the dictionary of numbers browser plugin adds alot of context the prices, especially for non-US readers:

    “Well-made but entry-level watches with genuine, hand-crafted tourbillons fetch at least $50,000 [≈ Median US household income, 2009]. The really good ones start at about $250,000 [≈ Median new home sale price, 2010].”

    1. Actually, seagull tourbillons are insanely cheap for the single axis ones. Theres tonnes of chinese tourbillons now like the aatos tiago and seagull tourbillon. Be sure to keep an eye out for them if youre an avid watch enthusiast wanting to score a bargain haha.

      who cares if the tourbillon itself is accurate or not? the chinese somehow managed to create one that “works”

        1. It is like the junk-fron-Japan trope of the 50s and 60s, it was simply possible to make a lower end product with cheaper inputs and cut corners as the wages were that low vs US$, in China the same is true but also with many subsidies available that after free shipping China is paying you to take their stuff. Eventually the better than shoplifting from China will end because people there will surely realize they are not getting paid; wacky work ethics and hope only go so far.
          That said I have gotten good tools and have seen military weapons and aircraft manufactured in China; if the price is right good to great quality can be made in China, but you screw yourself a little every time you ask for a discount and do not have QA actually in China. They cant do the bleeding edge of aerospace, heavy industrial machines, and electronics but in their niche they do just fine spending little until recently on the research base to surge ahead.

          1. “Eventually the better than shoplifting from China will end because people there will surely realize they are not getting paid; wacky work ethics and hope only go so far.”

            Except there is many Chinese waiting to take others place as slaves and the government encourages the whole scheme.

            The only way to stop junk coming out of China is to stop buying it but that won’t happen soon.

  3. I love mechanical watches, to me they are like a concealed model train set on my wrist.
    The problem is I beat the hell out of my watches, so my GMT(not rolex) is currently in a drawer while it waits for something like repair number 30.
    My eyes are getting weaker every year and my hands less steady, my affair is getting long in the tooth when a LCD quartz gets the job done no matter how gauche it is damn reliable.

  4. If only phones didnt need charging several times a day also.
    Ok so the clock stays accurate while its on but the battery sure as hell fades over the duration of its life.

    Balance battery anyone?

      1. I like my portable computer thank you very much… being bound to charging it every day is a small price to pay for the plethora of benefits I gain out of it both personally and professionally.

      2. In the event that works for you fine, but many of use use our phone for other handy purposes. To insure the actual phone function is available when I need it it’s recharged at least every night. So far my phones have been trouble free until I get another subsidized phone when the 2 year contract is renewed.

    1. People pay extra and line up outside Apple stores for phones that need to be charged multiple times per day. They also pay good money for torn jeans. And push metal through their nose. I’d better stop now, I’m getting depressed.

      1. These damn kids with their ball point pens and multi-cellular organisms, back in my day we had to fuse hydrogen to get anything other than hydrogen!
        And we liked it fine that way, now get off my damn lawn!

    2. I normally have to charge my phone every 2-3 days. But I don’t consider the phone a clock or watch. It can be used as a a substitute for a pocket-watch, but I want a wristwatch, digital with no clock hands. Mine has a solar cell which works very well since many years. So I do not need to change a battery or wind up a – much less accurate – mechanical watch.

  5. It’s funny, in the old days you had to wind a watch once or twice a day, now you need to recharge a smart watch several times a day.
    The difference? Winding you can do anywhere and anytime, charging needs a powersource and charger and you need to keep it in a safe spot so they don’t steal your stuff.

    But hey, at least now it tracks your every move (and heartrate and communications) for your glorious companies and government.

    1. Saying this gives me an idea, a pocket clip for suits with a solarcell outside (gold rimmed I’d say) and a charging connection in the pocket, then at least you can carry the thing with you while it charges and businesspeople wear their suit constantly so it would be a steady setup..
      Needs to be a good solar cell that can charge from indoor lighting though.

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