Tag Archives: Spring Drive

Watch movement types

As you probably already know, my other passion are watches. So, I’ve decided to start a new blog category dedicated to watches. I’ll start with the most important component of the watch. Its heart, the movement. So, lets start 🙂

What is movement?

Movement is a term used with watches that describes the watch heart (its engine) as a whole. There are several movement types that I’ll describe below and they are further divided into calibres (calibers).

What is calibre?

Calibre means a certain model of a specific movement. It can either mean a grade or a movement complexity along with many other things like finish or functions.

Movement types

– Mechanical handwind
Mechanical watches don’t use any batteries, they are, like the name suggests, entirely mechanical, driven by a coiled spring that provides mechanical power to run watch hands that then show you the time on the watch dial. User has to regularly turn watch crown (time adjustment knob on the side of the watch case) in order to wind the main watch spring which then provides the power to the watch. If you forget to wind it regularly, the watch will stop. Users of hand wind watches usually form some sort of daily routine where they wake up, wind the watch first and then continue with their day. The accuracy of timekeeping is usually +- 5-20 seconds a day, depending on the calibre grade. You can recognize such watch by listening to it closely and you’ll hear ticking inside. Second hand is also gliding quite smoothly across the dial.

– Mechanical Automatic
They are essentially the same as hand wind watches, what’s special about them is that they don’t require any special attention unlike hand wind mechanical watches. All that you have to do with Automatic watches is to wear them. Wearing them makes the special mechanism inside the watch to automatically wind up the main spring. So, for as long as you wear it, it will run, because the movement of your wrist will constantly charge the watch. In theory, Automatic watches can run for decades without any special maintenance or battery replacement. Their accuracy may degrade over the years, but some work perfectly fine even after 2 or 3 decades. Which is quite a lot of time. Typical power reserve of Automatic watches is 40 hours, but better and more expensive models can run for even longer without any motion (up to 80 hours and more). They have the same accuracy as hand wind mechanical watches. These tick just the same as hand wind models. Second hand is also gliding quite smoothly across the dial.

– Battery Quartz
Quartz movements powered by batteries are most common these days. Very accurate, very low maintenance and easy to use. And also the cheapest. Battery is powering the electronic circuitry with quartz crystal that vibrates at very specific frequency, which is then used as a reference to display accurate time. They can also sit still somewhere for several months and they won’t stop (unlike mechanical watches). Some battery powered watches can last up to 10 years without battery change, but most of them last for around 3 years before you have to replace the battery. Accuracy is usually within +- 10-30 seconds a month. You can recognize such watch by observing the second hand motion, which is ticking in 1 second intervals to conserve battery.

– HAQ Battery Quartz
HAQ or High Accuracy Quartz is exactly the same as the normal quartz, except it’s vastly more accurate. Usually rated at +- 10 seconds a year. They can achieve this by adding a thermal sensor and predefined settings how quartz crystal vibration frequency is compensated depending on temperature. Things tend to run slower in cold, so the electronics automatically compensates for that. Same applies for hot conditions. And this way, it can reach such high accuracy. Normal quartz watches are usually adjusted at a fixed value for an average temperature when the watch is on the wrist. Second hand on these ticks in 1 second intervals as well, however Bulova Precisionist watches are the only HAQ grade watches that don’t use thermo compensation and they have a smoothly gliding second hand.

– Automatic Quartz (AutoQuartz or Kinetic)
These behave the same as battery quartz watches, but they don’t require battery changing. Special mechanism inside the watch converts your wrist motion into electricity which is then stored into special rechargeable battery already inside the watch. These are just as accurate as battery powered quartz watches, but they don’t require battery changing. Integrated battery can last even to 30 years or more if everything goes well and power reserve when the watch is not moving is usually from 6-12 months. It is recommended not to leave these watches to completely run down of power as that damages the integrated rechargeable battery. Most widely sold and known are Seiko Kinetic watches, but several Swiss companies also offer them, usually under AutoQuartz brand or something similar. Second hand is ticking in 1 second intervals, but goes into 2 second intervals when battery power reserve is very low.

– Solar Quartz
These are designed in a similar way as Automatic Quartz. Except they don’t make electricity with mechanical motion, they instead create electricity using solar cells hidden underneath the watch dial. Keep the watch in enough light and it will run for as long as those Automatic Quartz watches without any maintenance. Solar watches don’t mind sitting still somewhere for as long as there is some form of light. But they don’t like dark places, like drawers for example as they will drain power and stop after several months. And this also damages their integrated rechargeable battery. So, never let them run down completely. Best known watches using solar technology are Citizen Eco-Drive and Casio Tough Solar. Second hand is ticking in 1 second intervals, but goes into 2 second intervals when battery power reserve is very low.

– Solar-Automatic Quartz Hybrid
Only Citizen attempted this by combining solar cell and mechanical power generator, the watches were of higher price range and they failed to attract enough customers so the Citizen canceled this movement and focused on solar technology only. Luckily for them, it was a huge success, that’s why you can find Eco-Drive movements in nearly every single Citizen watch.

– Quartz-Mechanical Hybrid (Spring Drive)
There were some prototypes from Swiss companies, but Seiko was the first to use it in commercially available watches that are now sold like any other watch. They call this technology “Spring Drive”. Quite expensive, but a beautiful marvel of its own. What is special about this watch is the way it works. It’s a blend of old school mechanical technology paired with high tech electronics. Wrist motion winds up the main spring inside (just like with mechanical Automatic watches) which then functions as dual purpose power source. First one is a mechanical force provided to move the watch hands. The second one is a tiny power generator that creates electricity from main spring unwinding. This on-the-fly generated power is then used to power quartz crystal oscillation (a timekeeping reference) and something Seiko calls “Tri-Synchro Regulator”. It’s an electromagnetic regulator, electromagnetic brake if you want, that controls the unwinding of the main spring. If there was no regulator, it would unwind in a matter of seconds. But with the help of Tri-Syncro regulator, it unwinds at a highly accurate rate which provides Spring Drive watches with 1 second per day accuracy, which is around equal to the battery quartz watches. But it requires no batteries at all, it has no rechargeable battery inside and its power reserve is 72 hours. You can recognize these watches by a “Spring Drive” text on the dial and a very special perfectly smooth second hand gliding without any ticking. It glides so smoothly its nothing like you’ve seen in any high end mechanical or quartz watch. Even the above mentioned Bulova Precisionist doesn’t actually glide. It just ticks at very fast rate so it makes the second hand appear it’s gliding.

http://www.seikospringdrive.com

– Thermoelectric Quartz
Thermoelectric quartz watches use effect called Seebeck effect to generate electricity and store it in a rechargeable battery like solar and kinetic watches do. It’s a thermoelectric process where electricity is generated from a temperature difference on each sides of the power generating unit. You can read more about Seebeck effect on the link below… It generates power with Seebeck effect, where the heated side is wearers wrist and the cold side is the atmosphere (air) around the watch. Downside is that such watch only works in colder environments, but doesn’t operate too well in more tropical places, because there is very little or no temperature difference between wrist and atmosphere. And if there is no difference, the watch will not generate any (or too little) power and it will eventually stop working. The first watch using such technology was Seiko Thermic, which was unfortunately discontinued. It’s a pretty nice looking watch and if you really want it, you can still find used Seiko Thermic watches. But expect higher price since it’s a rather rare piece of machinery 🙂

http://en.wikipedia.org/wiki/Thermoelectric_effect

These are some rough basics, I’ll keep on writing new articles with descriptions of other parts and technologies around watches. Stay tuned if you’re interested. Or you’ll become interested. It maybe sounds geeky and maybe even is a bit, but once you get into this, it’s actually very addicting and interesting hobby.

EDIT (2013-11-25)
– Added Solar-Automatic Quartz Hybrid and Thermoelectric movement movement types