All watches on todays market are either quartz or mechanical. A quartz watch derives its power from a battery or solar cell; whereas a mechanical watch takes its power from the energy released by wound spring. Mechanical watches can be either manual or automatic.
A manual mechanism is a typically hand wound movement, dating back to the 16th century, now mostly found in high-end and collectible watches, often featuring exhibition, or “skeleton” dials and case-backs. Manual movements need to be wound daily, and should never be wound past the first feeling of tension, for fear of damaging the mechanism.
The essential parts of manual movement are:
- The crown (1), which when turned, winds the main spring.
- The main spring (1) stores power which is transferred through a series of gears to the escapement.
- The escapement (2&3) acts a brake of sorts, funnelling the power from the gears into equal measures through to the balance wheel.
- The balance wheel (4) oscillates between 5 and 10 times per second, moving energy transferred from the main spring, to the dial train.
- The dial train (5) moves the hands (6) and date dial (if present), at the correct speed to keep an accurate time shown.
The jewels are used in places of high-friction to dissipate heat that may affect the mechanism.
The automatic mechanism is identical to the manual movement, with the addition of a weighted rotor (1) above the main spring that winds the movement as it’s worn, and moved throughout daily life. Consequently, this means the watch is self-winding, and therefore “automatic”.
Quartz movements are typically battery or solar powered, and are considered the most accurate watch mechanism, due to the design. Lasting from 12 months to 3 years, the power cells for quartz powered watches are readily available, and easily serviced by most jewellers.
- The power source, be it battery or solar cell, takes the place of the main spring to power the inner workings of the watch, without any winding or external interaction needed.
- The integrated circuit carries the power from the power cell to all the relevant part of the watch. (LED, external sensors, etc.)
- The integrated circuit also send current to the quartz crystal which vibrates at a rate of 32,768 vibrations per second (also known as Hertz). Every 32,768 vibrations a current is sent to the stepping motor behind the dial.
- The stepping motor converts the electrical current into mechanical power, and sends it to the dial train (for analogue watches), or the LCD display (for digital watches).
- The dial train on a quartz movement performs identically to the dial train on a mechanical or automatic watch.
Notable additions to the standards are advances in technology which have advanced the world of watches are things such as:
- Citizens’ Eco-Drive, which uses both natural and artificial light to charge a photovoltaic solar cell that powers the quartz movement.
-Seiko mastered a different kind of mechanical movement with the Kinetic Auto Relay, which stop all visible movement after 72 hours of no motion, but can keep accurate time for up to 4 years. Once picked back up, the hands swing round to show the current time.
-Breitling have developed their own mechanical chronograph movement which helped to redefine this complication. Also, Breitling have equipped all their battery powered watches with their own proprietary SuperQuartz movement, which can achieve up to 10 times the accuracy of a regular quartz movement.
- Omega redeveloped the mechanical movement in a way for over 250 years, introducing the Co-Axial escapement, which reduces friction using lateral impulses to allow for greater accuracy in chonometric performance.