Automatic quartz

Automatic quartz is a collective term describing watch movements that combine a self-winding rotor mechanism (as used in automatic mechanical watches) to generate electricity with a piezoelectric quartz crystal as its timing element. Such movements aim to provide the advantages of quartz and mechanical watches. Several manufacturers employ this technique.

Mode of operation

Lorus (a Seiko brand) watch with glass back, showing clearly the swinging pendulum and meshing gear and pinion of the Seiko Kinetic movement

A rotating pendulum inside the case is attached to a relatively large gear which meshes with a very small pinion. As the wearer moves, the pendulum turns and spins the pinion at a very high speed - up to 100,000 rpm. This is coupled to a miniature electrical generator which charges three or four small capacitors. If the watch is left off the wrist, the capacitors can store enough charge to power the watch for longer periods than a mechanical automatic watch. A typical full charge will last between two months and six months. Charge from the capacitor drives a conventional quartz watch mechanism accurate to 1-2 seconds per week. On the 5M62 series movements where the total energy storage time is stated at six months, the charging from a typical days wear appears to be approximately two weeks worth.

Applications

Seiko

Japanese company Seiko pioneered the technique which it unveiled at the Baselworld 1986 under the trial name AGM. The first such watch was released in Germany in January 1988 and April of the same year in Japan (under the name Auto-Quartz). The watches had an average monthly rate of ±15 sec and provided 75 hours of continuous operation when fully powered. Early automatic quartz movements were called AGS (Automatic Generating System); in 1991 the company introduced the Kinetic brand name. Today Seiko offers a wide range of watches with various different Kinetic movements. The top of the line is the caliber 9T82, included in Sportura (international brand) and PROSPEX (only marketed in Japan) Collection. It's sold in limited volume at a price range of about US$3000 which makes it one of the most expensive automatic quartz watches. Kinetic technology has also been used in some of Seiko's Pulsar and Lorus watches. As of 2007, Seiko has sold more than eight million automatic quartz watches.

Technical advances by Seiko include:

• Auto Relay, if the watch is stationary for 72 hours that stops the analog hands in order to conserve power during long periods of inactivity, and can maintain a record of the correct time for four years, as well as,
• Perpetual Calendar which is the first Kinetic calibre combining Kinetic technology, Auto Relay capabilities, and a perpetual calendar correct until February 28, 2100.
• Direct Drive, the possibility of winding the watch manually by the crown. Watches equipped with Direct Drive will also display the power generated by manual winding, as well as the total power reserve.

The different calibres of Kinetic watches currently are relatively large and heavy, weighing in at 1/3rd of a pound or more on many models. Therefore, most Seiko Kinetic watches are only available in a men's size.

Movement calibers

• 1M20
• 3M21 3M22
• 3M62
• 4M21
• 4M71
• 5D44* (Direct Drive)
• 5J21* 5J22* (Auto Relay)
• 5J32* (Auto Relay)
• 5M22 5M23 5M25
• 5M42 5M43 5M45 5M47
• 5M62* 5M63* 5M65(GMT)*
• 7D46* 7D48* (Auto Relay, Perpetual Calendar)
• 7L22* (Auto Relay, Chronograph)
• 7M12 7M42
• 7M22 7M45
• 9T82* (Chronograph)
• YT57* YT58*

(*) In use as of at Aug-2007

Implementation faults

• Some calibers have the backlash phenomenon; tilting the watch from side to side occasionally caused the minute hand to fall around somewhere between half a minute and a full minute. It was confirmed by SEIKO and technically it is impossible to improve the situation by reassembling the watch. This however is apparently completely normal for quartz watches generally. It is more commonly a slight play in the minute hand seen in Seiko quartz movements that amounts to perhaps 1/12th to 1/6th of a visible minute between minute notches on the dial. Argumentatively, this is not a practical problem and is only noticeable when the case is held motionless and the long hand is watched repeatedly and singlemindedly. Furthermore it only occurs rarely, at least in Seikos with movements manufactured in the last 15 years. Most of the time, the minute marks are hit either dead on, or so close as to hardly be noticeable. Also this does not effect the actual time keeping in the slightest, which is very precise, even by quartz watch standards. As noticed, it appears that any tendency for the long hand to come up short by the same fractional distance is related to the date dial turning at the same time between 2200 and 0000. The amount of actual daily time when this would occur is only about one hour.

• Some watches made before year 2000 brought faulty capacitors in the ESU (Electricity Storage Unit). Newer models already bring a new lithium ion rechargeable cell. This cell, sometimes called a secondary battery, enabled the ESU to store more energy for a longer period of time. With the currently made 5M62/5M63/5M65 movements, the result is reserve power for up to six months. An older Kinetic caliber like the 5M42, only runs for two weeks on it's reserve power. It also eliminated some capacitor related issues in some Kinetic models in the mid and late 1990s.

ETA

Swiss company ETA SA, part of the Swatch group, also manufactures automatic quartz movements, calling them Autoquartz. These are then used under the Swatch brand or sold to third-party companies. However, ETA - unlike Seiko - has had little success to spur demand for the product and few watch models have so far been released. As of 2007 most Autoquartz products have been taken off the market.

Movement calibers:

• 204.901
• 204.911 (power reserve: 60 days)
• 205.711
• 205.911 (power reserve: 100 days)
• 205.961

Manufacturers who employ or employed ETA movements: Tissot, Longines, Swatch, Omega (Omega Seamaster Omega-matic), Dugena (K-Tech), Invicta (9179), Hermès (Nomade), Roberge (Altaïr), Mido (Multifort), Bovet (Autoquartz calibre 11BQ01), Fortis (Spacematic Eco) and Cyma.

Citizen

Citizen, the second largest Japanese watch company (after Seiko), also built an autoquartz-powered watch: the Citizen Promaster Eco-Duo Drive (released in December of 1998). Novel to this watch was the use of both mechanical power as well as a solar cell. This model was an attempt to enter higher-priced markets (at a cost of around $1000 USD) but the technology failed to attract consumer interest and Citizen has since stopped making use of the unique movement. No other autoquartz powered watch from Citizen is known, all other Eco Drive models only use solar power.

Ventura

Ventura is a small Swiss watch manufacturer claiming to be "the World's only manufacturer of automatic digital watches". Their VEN_99 movement is indeed the only watch combining autoquartz and digital readout of time (LCD) in one package. On offer are three models: the Sparc rx, fx and px. In late 2006 the company will start selling their new movement incorporating alarm which would make another exclusive feature. All hardware is genuinely designed and exclusively sold by Ventura.

Critique

• As a result of the relatively complex mechanical parts used, such watches tend to be more expensive to manufacture and service.
• Although they are a hybrid of mechanical and electric parts and provide substantial advantages over entirely mechanical watches, these movements do rarely or never appeal to watch collectors and connoisseurs interested in higher-priced and up-market models which are nearly always mechanical.

See also

• Automatic watch
• Complication (horology)

External links

• watches-lexic: ETA Autoquartz

• Seiko AGS Quartz Watch The world's first automatic power generating quartz watch.