How does an automatic movement work?

When selecting a new watch, it is not only the shape and colour that are decisive. And not just the dial, the number of hands and the design, the date or not. Of course, many also wonder whether it is worth investing more and buying a watch with automatic drive. But if you want that, you should know how an automatic watch works.

The origin of every movement in a mechanical movement is power. This force is necessary to store the tension spring packed in the mainspring barrel. Sounds complicated but is simply explained. An automatic movement is basically a normal mechanical movement with a sophisticated additional mechanism. This sophisticated add-on converts kinetic energy into potential energy. Quite simple: When the wearer of the automatic watch is in motion, this motion is used to tension the tension spring. This means that all automatic movements are based on the same basic principle. With the help of kinetic energy, a ball-bearing rotor transfers flywheel mass to a spring. This tensions the tension spring. Very simple. Many automatic watches have a visible base, which means that the rotor is easy to recognize. If one sets the clock now in motion one sees like the movable rotor, and thus the uppermost part of the clockwork also oscillates. It is in the nature of things that the spring wants to return to its original, unstressed form – this generates the drive force mentioned above. The resulting energy is transferred to the gear train. This consists of minute wheel, intermediate wheel and fourth wheel. Figuratively speaking, the gear train can be imagined as successively connected gear wheels. Directly coupled to the mainspring barrel is the large minute wheel, which absorbs the driving force of the spring as the first unit. It takes exactly 60 minutes for the minute wheel to complete a complete revolution.

But how does the time get on the dial? The so-called minute tube connects the wheel with the minute hand on the dial. The intermediate wheel is connected downstream of the minute hand. The intermediate wheel in turn is connected to the fourth wheel. This fourth wheel needs exactly 60 seconds for one revolution. Actually logical. Now we come to the function of the escapement. The task here is to bundle the driving force, i.e. to inhibit this force. The energy of the mainspring barrel should not be released too quickly – hence the term escapement – this function ensures the right timing.