Automatic quartz


Automatic quartz is a collective term describing watch movements that combine a self-winding rotor mechanism to generate electricity with a piezoelectric quartz crystal as its timing element. Such movements aim to provide the advantages of quartz without the inconvenience and environmental impact of batteries. Several manufacturers employ this technique.

Mode of operation

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 a storage device which is a capacitor or a rechargeable battery. A typical full charge will last between two weeks and six months.

Applications

Seiko

Japanese company Seiko pioneered the technique which it unveiled at the Baselworld 1986 trade show under the trial name AGM.
The first such watch was released in Germany in January 1988 and April of the same year in Japan. 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.
In 1991 the company introduced the Kinetic brand name.
Today Seiko offers a wide range of watches with various Kinetic movements. The top of the line is the caliber 9T82, included in Sportura and PROSPEX Collection. It is 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.
The different calibres of Kinetic watches currently are relatively large and heavy, weighing in at 1/3 of a pound or more on many models. Therefore, most Seiko Kinetic watches are only available in a men's size.
Movement calibers:
In use as of at Aug-2008

ETA

Swiss company ETA SA, part of the Swatch group, made seven different automatic quartz movements, calling them Autoquartz. They were part of the premium Flatline series of movements and were sold to a variety of watch vendors, primarily European and American. High grade movements designed to last as long as their premium mechanical movements, they had between 15 and 53 jewels. Unlike most quartz watches, Autoquartz could be calibrated to increase their accuracy. Several vendors had their Autoquartz watches COSC certified. In 2006 to increase production of its highly demanded mechanical movements, Swatch discontinued supplying the Autoquartz line to customers. Then in 2009, possibly due to available production capacity or stocked parts, Tissot reintroduced the Autoquartz in its PRC200 dive watch. The Autoquartz movement used by Tissot is gold plated and carries the designation ETA 205.914.
Movement calibers:
Manufacturers who employ or employed ETA movements: Tissot, Rado in their Accustar line of watches, Longines, Swatch, Omega, Dugena, Wenger, Hermès, Roberge, Mido, Bovet, Fortis, Belair, Franck Muller, HTO and Cyma.

Citizen

, one of the world's largest watch manufacturers, also built an autoquartz-powered watch: the Eco-Drive Duo. 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, 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 or thermal 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 was the only watch to ever combine autoquartz and digital readout of time in one package. Offered were three models: the Sparc rx, fx and px. In late 2006, the company started selling their movement with an incorporated alarm, another exclusive feature. All hardware is proprietary to Ventura.
In 2007 the company went into bankruptcy. Support was available from an independent entity. In 2011 the company re-emerged from bankruptcy and continued to sell its models, introducing the "2nd gen Micro-Generating-System" and marketing the watch integrating it as the world's first and only digital-readout multi-function automatic quartz module. Unlike with other manufacturers the watch movement and power source are separate units, only linked by a single wire.

Pricing

In spite of the relatively complex mechanical parts used, Seiko has positioned their kinetic watches to be medium-priced. Exceptions are kinetic with other complications such as chronograph movement 9T82, 7L22 and direct drive movements. ETA sold Autoquartz to a variety of Swiss manufacturers with pricing below $100 to multiple thousands. Ventura prices its automatic quartz watches at around 2000-4000 Euro.