Understand the mechanisms of an automatic watch ? Beaubleu tells you everything


Understanding the mechanism of a watch is not always obvious. In the common mind, a watch is battery operated or manually wound. However, automatic watches have a very particular specialty. Let’s find out together.


What is the automatic mechanism?

The automatic watch has its origins in the manual watch. Its mechanism is made up of many elements which, when assembled together, allow this marvelous mechanism to be put into action. Its master piece? The rotor (also called “oscillating weight” or “inertia block”). It is the rotor that makes it easier to start the watch’s gears by swinging the wrist.

Thus, as long as it is worn, the mechanism of the watch winds itself. If the owner does not wear it on his wrist, this type of watch has an autonomy of 40 hours on average. This is why these models are equipped with a crown that allows them to be adjusted again if the device is stopped.

If you opt for this mechanical jewel, you will have to be careful not to exhaust the power reserve in order to avoid the need for manual winding.

Focus on the mechanism of the automatic watch

To fully understand the mechanism of an automatic watch, let’s take a look at its components and how they work.

  • The rotor : this is the weight we mentioned above. In the form of a semi-circle turning 360 degrees when it is in motion, it is the rotor that provides the energy to the watch mechanism.
  • The spring : in the form of a ribbon wound around the barrel (cylindrical part), it plays the role of the motor. In other words, it accumulates all the energy produced by the rotor in order to release it to the rest of the mechanism.
  • The transmission system : the mission of this small gear is to transmit the mechanical energy distributed by the spring directly to the escape wheel.
  • The exhaust wheel : after having received the energy from the transmission system, this gear will let it diffuse intermittently in a regular way.
  • The balance wheel : with a beat going from 5 to 10 times per second, it is the heart of the movement. It regulates the circular swing of the hands.
  • Rubies : they are not real precious stones. Synthetic, hard and resistant, they reduce friction and therefore wear.
  • The crown : it is used to manually wind the mechanism of the watch. It is a kind of button external to the device that also allows to set the time accurately.
Beaubleu collection Union montre automatique aux aiguilles rondes Olympe fond de boite avec mouvement Miyota 9015