Moreover, how does an automatic watch work? An automatic watch is a mechanical watch that winds itself. If you have ever wondered how does an automatic watch work, the interactive movement above shows the whole story: a mainspring stores energy, a gear train passes it on, and the escapement releases it in tiny equal steps while the balance wheel keeps time.
How does an automatic watch work? The five parts you just played with
- Mainspring barrel: a coiled spring that stores the energy.
- Gear train: reduces the spring speed to the pace of the hands.
- Escapement: the escape wheel and pallet fork that create the tick.
- Balance wheel and hairspring: the regulator that sets the rate.
- Rotor: a weighted half-disc that winds the spring as your wrist moves.
How the rotor winds the watch
Therefore, every time you move your arm, the rotor swings and turns the mainspring through a small gear system. A full wind typically lasts around 38 to 80 hours, depending on the movement. If you take the watch off for a weekend, it may stop, and a few shakes plus a turn of the crown will restart it.
Automatic vs quartz
An automatic uses a spring and gears and needs no battery, while a quartz watch uses a battery and a vibrating crystal. See our interactive quartz guide to compare. Automatics are usually a few seconds a day off, quartz a few seconds a month. In short, this is the answer to “how does an automatic watch work?”
Where to start buying
If this made you curious, browse our picks for cheap automatic watches or watches under $500.
Now that you know how does an automatic watch work, you can shop with confidence. For more background, see the Wikipedia article.
How does an automatic watch work: FAQ
Do automatic watches need batteries?
No. The movement runs on the energy stored in the mainspring.
Can an automatic watch be overwound?
No. Modern automatics have a slipping clutch that stops the spring from over-tightening.
Why did my automatic watch stop?
Similarly, it most likely ran out of power reserve. Wear it for a day or wind the crown.
