====== Peripheral rotor ======
A **peripheral rotor** [[automatic movement]] places the [[weight segment]] used to wind the watch on a track outside the movement itself.

===== Overview =====
The peripheral rotor turns outside the movement, though typically still on the [[plate]]. It interacts with gears set into the side of the movement to wind the [[mainspring]]. This is in contrast to a [[central rotor]] movement, which mounts a full-width weight segment on a bottom-mounted bearing at the center, and [[micro-rotor]] which uses an integrated, smaller weight segment inside the movement.

This unique design allows the entire movement to be viewed through a [[display caseback]] and allows the company to install modules on both sides if needed. One challenge of a peripheral rotor system is the location of the [[stem]] and [[crown]] Patek Philippe mounted these to the back of the movement, while the Carl F. Bucherer movement was thicker, allowing a traditional side position.

===== History =====
Peripheral winding took many years to come to market. The concept was first patented in [[1955]] by [[Gosteli, Paul|Paul Gosteli]] but did not reach production. A similar design was patented in [[1965]] by [[Patek Philippe]] and came to market in [[1970]] in limited production as [[PP 350|Cal. 350]]. However Cal. 350 was widely regarded as unreliable, even after an update in [[1979]] with uni-directional winding. The entire series was retired in [[1985]].

[[Citizen]] also produced a variation on the peripheral winding theme with their [[Citizen Jet]] of the 1960s, but this was more of a geared [[central rotor]] and did not run around the periphery of the movement.

[[CFB A1000|Cal. CFB A1000]], introduced by [[Carl F. Bucherer]] at [[Baselworld]] [[2008]] after three years of development, was the first mass-produced peripheral rotor movement. The new [[manufacture]] developed many new technologies to bring the peripheral rotor to production, as well as a shock protection system for the balance spring carrier stud. The first watch to be produced with Cal. CFB A1000 was released for sale in [[2009]], by which time other manufacturers were working on similar technology. [[De Witt]] would introduce [[DW 8014|Cal. DW 8014]] in [[2010]], [[Audemars Piguet]] would follow with [[AP 2897|Cal. 2897]] in [[2011]], and [[Cartier]] with [[9603 MC|Cal. 9603 MC]] in [[2012]].

===== See Also =====
  * [[Central rotor]]
  * [[Micro rotor]]


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