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 without the environmental impact of batteries. Several manufacturers employ this technique.

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(s) or a rechargeable battery. A typical full charge will last between two weeks and six months.

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 (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 Kinetic movements. The top of the line is the caliber 9T82, included in Sportura (international brand) and PROSPEX (only marketed in Japan) 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 (150 grams) or more on many models. Therefore, most Seiko Kinetic watches are only available in a men's size.

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