How Watches Work

1. MECHANICAL MOVEMENTS If a watch is said to have mechanical movement, this means that the watch has a device for keeping time, which uses the energy from a wound spring, and keeps time through the highly regulated release of that energy through a set of gears and an escapement. This device must be wound periodically, ensuring that the wound spring is continually loaded to power the watch. It differs from the typical quartz watch in that it uses purely mechanical components to keep time. A normal mechanical watch can run for about 40 hours on one full winding of the mainspring, and a few designs can last up to 8 or 10 days are also available. The general design of mechanical movement watches have not changed notably in the past fifty years. But, the development of greater technology and modern materials has changed the way mechanical movement watches are manufactured.


2. AUTOMATIC MOVEMENTS Watches that are powered by automatic movements operate similar to a watch with mechanical movements, except that the winding of the spring occurs automatically, every time the wearer moves his or her arm. A rotor that turns in response to motion winds the watch's mainspring, supplying the needed energy to power the watch. The obvious benefit of an automatic movement is that there is never a need to replace a battery or to wind the watch. Keeping this in mind, it is necessary to occasionally "tune up" an automatic watch to ensure timekeeping is precise.


3. QUARTZ MOVEMENTS Watches that have quartz movements are a relatively new development in watch history. Quartz crystals have a unique property in that when they are compressed or bent, they conduct a constant voltage, or pulse, on their surface. This constant voltage is what is used to power quartz watches with exact precision. Rather than a wound spring (mechanical movement), quartz watches rely on a battery for their energy. The battery sends electrical energy to the tiny quartz crystal, which in turn creates a pulse at regular, constant levels. Because the pulse, also called an impulse, is extremely constant, quartz movements ensure precision timekeeping, down to hundredths of a second. To convert the impulse into a steady power that can move the watch hands at regular intervals, the impulse is simply passed through a stepping motor that converts the electrical energy of the impulse into mechanical energy that is needed to run the watch. Since the early 1970's, quartz watches have become very popular, for both manufacturer and consumers, due to the fact that quartz watches are less expensive than mechanical movement watches and can be easily manufactured in large volumes.

   SOLAR Solar powered watches are one of the latest technological advances in watch development. Solar powered watches contain a light sensitive receptor underneath the dial, which absorbs light (natural or artificial), and converts it into energy to keep the watch ticking. This captured energy is stored in a small permanent battery in the watch so that the watch still functions in the dark. One of the most popular and well known solar powered watches is the Citizen Eco-Drive watch.

   KINETIC or Hybrid Automatic/Quartz watches use the movement of the watch wearer's arm to produce the electrical energy to keep the watch running. Once a kinetic watch is fully charged, it can normally run for a long period of time (some up to 6 months) without being recharged. The energy for Kinetic watches is stored in a capacitor that keeps the watch on time even when it is being stored. Kinetic energy watches do not require a battery and have no need for winding. A good example of a watch that uses kinetic movement to power the watch is Seiko's Kinetic watches.

4. ATOMIC MOVEMENTS Atomic watches offer unmatched, split second accuracy by automatically synchronizing several times daily via radio signal with the National Institute of Science and Technology's (NIST) atomic clock in Fort Collins, Colorado, the most accurate clock in the world (accurate to within 1 second every million years). Atomic watches also adjust automatically from time zone to time zone and for leap years and daylight savings time. Typically atomic watches have quartz movements to keep time between synchronizations with NIST. One of the most popular atomic watches are manufactured by Oceanus watches.