Montres automatiques: comment ça marche ?

Automatic watches: how does it work?

A real feat!

The automatic watch is undoubtedly a must for all fanatics of watches and automation, indeed the man has succeeded in creating a hyper ingenious and elaborate system, a watch that is automatically wound by the wearer.
True performance that exploits the full potential of kinetic energy, this mechanism is no longer a secret. So here is explained in detail how an automatic watch works !
Our automatic watches

What is an automatic watch?

The watch is an extremely complex gadget, at the heart of which is an intricately crafted mechanism that allows the hands to turn in exact rhythm with the passage of time . On the other hand, all watches do not have the same mechanism, also called movement by watchmakers. Watches with a mechanical movement , unlike quartz watches, do not use a battery, they only work thanks to an assembly of wheels and springs.
Considered as the noblest, automatic watches are self-winding mechanical watches not to be confused with simple mechanical watches that must be wound by hand (At LIGE you will only find automatic watches )

Invention and evolution of the automatic movement

Historians are not unanimous about the origin of this invention. For some, it is the Swiss Abraham Louis Perrelet who invented this device in 1777 , for others it is the Liègeois Hubert Sarton in 1778 with a rotor winding .

This device was only massively used with the advent of wristwatches at the beginning of the xx th century. Using a weight (rotor) which rotates 180° back and forth when the wearer of the watch is in motion, he managed to create an automatic system!
In its early days, this automatic movement had a fairly short lifespan of barely 12 hours. It was therefore not necessary to leave the watch too long without a movement! In the 1930s, the Rolex brand brought an improvement to the mechanism, this thanks to a weight this time semi-circular and rotating 360°, it was then able to offer automatic watches with a 35-hour power reserve. Much more practical for daily use, which will make it a great success!

How it works ?

Instead of using a battery and an electrical circuit that make the hands turn at the right pace, it's the weight (rotor)  which provides energy to the mechanism as soon as the watch moves. This weight also turns very easily , in fact all you have to do is wear the watch, and at the slightest movement you make with your wrist, the mechanism starts working and it is fed. And so, quite logically, if a mechanical watch remains static and resting on a piece of furniture for too long (several days), it ends up no longer working. No worries! All you have to do is wind it up, put it back on your wrist and it's ready to go again.

What is the internal mechanism made of?

To achieve this masterpiece of watchmaking whose lifespan is excellent , it is obviously necessary to call upon numerous internal components.

  • The impeller: Also called weight, or oscillating mass, it is the famous weight in a semicircle which rotates 360° when the wrist moves. It is fixed at the center of the movement and supplies the energy.
  • The barrel spring: It stores the energy produced by the rotor and restores it to the rest of the mechanism. This is a tape that acts as a motor.
  • The transmission system: A small cog, it takes over from the mainspring of the barrel and transmits the accumulated mechanical energy to the escape wheel.
  • The escape wheel: Also called an anchor wheel, its mission is to regularly and intermittently release the energy conveyed to it.
  • The pendulum: Considered the heart of the movement, it beats between 5 and 10 times per second in a circular fashion and it regulates the movement of the hands.
  • Rubies: These are hard and resistant synthetic stones that are installed inside the mechanism to reduce friction and wear.
  • The crown : External button to the mechanism, present on the case of the watch, it is used to manually wind it and adjust it precisely.

Finally, here is a diagram of the movement

  1. The wrist moves and sets the rotor in motion.
  2. The rotor rotates and in turn actuates the mainspring of the barrel.
  3. The energy then reaches the transmission system.
  4. The transmission system then transmits this energy to the escape wheel.
  5. The escape wheel releases energy on a regular basis.
  6. The pendulum receives this energy and beats at this same regular rhythm.
  7. Each beat transmits energy to the hands which then turn on the dial!
To thank you for reading our article, here is an exceptional offer of -10% on all our automatic watches with the code: BLOG10

So, convinced? Also take a look at our other watches .

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