Today let’s start with a rudimentary breakdown of a watch’s component. The graphic below shows the elements that nearly every watch will have.
Parts of a Mechanical Watch Movement
Below we’ve covered the major working elements / terms of a watches inner workings.
Balance Spring / Hairspring
The balance spring is a very fine spring in a mechanical watch that causes the balance wheel to recoil. The spring of the balance is also called hairspring (flat spiral) was invented in 1675 by Christiaan Huygens. The spring itself was originally made from steel or gold, and today is made from temperature resistant alloys or silicon.
The hairspring provides restoring force to the balance wheel, enabling isochronal oscillations. The inner end of the hairspring is attached to the balance staff and the outer end to a stud on the balance cock. The spring’s elasticity ensures that the balance swings back and forth at a regular rate. The active length of the hairspring interacts with the momentum of the balance rim to determine the duration of each beat of the balance. This is why most of mechanical watches are equipped with a regulator on the balance cock that can be adjusted to vary the active length of the hairspring. Lengthening the spring causes the watch to run more slowly, shortening it makes the watch run faster. The hairspring and balance wheel together are the regulating organ of the mechanical watch. This harmonic oscillator is very resistant to outside disturbances, which makes it especially suited to keeping track of time. The balance wheel and hairspring is very similar to the pendulum in a clock. The major difference is that the balance wheel and hairspring are portable, while the pendulum is not.
The balance wheel receives the lateral impulses from the escape wheel, and oscillates. The balance spring provides the restoring force to the balance wheel. The balance wheel is the second element to regulate time and is attached to the balance spring. As the balance spring coils, the wheel oscillates and divides time into equal segments. This mechanism regulates the accuracy and works the same way as a pendulum. Together, they are the regulating organ of the mechanical timepiece. This harmonic oscillator is very resistant to outside disturbances, which makes it especially suited to keeping track of time. The balance wheel and hairspring is very similar to the pendulum in a clock. The major difference is that the balance wheel and hairspring are portable, while the pendulum is not.
Used in mechanical watches and clocks, The barrel is a large gear that contains the powerful mainspring. The mainspring, when wound, provides power to the watch affecting Affecting the length of the power reserve on a watch. The barrel is a cylindrical metal box closed by a cover, with a ring of gear teeth around it, containing a spiral spring called the mainspring, which provides power mechanism. The spring is hooked to the barrel at its outer end and to the arbor at its inner end. The barrel teeth engage the first pinion of the wheel train of the watch, usually the center wheel. Barrels rotate slowly: for a watch mainspring barrel, the rate is usually one rotation every 8 hours. This construction allows the mainspring to be wound (by turning the arbour) without interrupting the tension of the spring driving the timepiece. Watchmakers have paid much attention to this component throughout the history of watchmaking. Ever since spring-driven watches hit the market, they have been trying to find the best watch design to encase their movements.
A bridge is fixed to the main plate, thus forming the frame of a watch movement which houses all other parts.
Calibre / Caliber
Originally, the caliber denoted the position and size of its components. Today, a caliber refers to the movement number, origins or its manufacturer. The movement or caliber is the working mechanism in a watch. For many years, watch enthusiasts have been debating the most precise movement: Is it a mechanical movement? a automatic mouvement or is it a quartz mouvement?