Automatic watch
A self-winding watch movement has a mechanism which winds the mainspring using the natural motions of the wearer's body.
[8] But his idea was probably based on the myth of perpetual motion, and it is unlikely that it was a practical solution to the problem of self-winding watches.
The earliest credible evidence for a successful design is the watch made by the Swiss watchmaker Abraham-Louis Perrelet, who lived in Le Locle.
In 1777 Abraham-Louis Breguet also became interested in the idea, and his first attempts led him to make a self-winding mechanism with a barrel remontoire.
Towards the end of 1778 he sent a watch to the French Academy of Sciences and a report was written which, together with a drawing, gave a detailed description of the mechanism.
About the beginning of 1779, Abraham-Louis Breguet became aware of Perrelet's watches, probably through Louis Recordon, who travelled from Geneva to London via Le Locle and Paris.
The advent of the wrist watch after World War I led to renewed interest in self-winding mechanisms, and all four types listed above were used: Invented by John Harwood, a watch repairer from Bolton, England, who took out a UK patent with his financial backer, Harry Cutts, on 7 July 1923, and obtained a corresponding Swiss patent on 16 October 1923.
The weight did not rotate a full 360°; spring bumpers limited its swing to about 180°, to encourage a back and forth motion.
[21] Like its 18th-century counterparts, Harwood's watch also had a problem with jerking because "the brass weight hit too sharply against the banking pins as it pivoted".
[citation needed] It did not have a conventional stem winder, so the hands were moved manually by rotating a bezel around the face of the watch.
Thirty thousand were made before the Harwood Self-Winding Watch Company collapsed in 1931 in the Great Depression.
Rolex's version also increased the amount of energy stored in the mainspring, allowing it to run autonomously for up to 35 hours.
This allowed Glycine to survive the global depression in the 1930s that caused many Swiss watchmakers to close shop.
Ball bearings provide robust support for a heavy object to rotate smoothly and reliably even under abnormal stress, such as if the watch were dropped.
However, in 2007 Carl F. Bucherer implemented a new approach without a rotor, a peripherally mounted power source, where a geared ring and a rotating unbalance mass segment made of tungsten encircles the entire mechanism, rotating on carbon rollers whenever the watch moves.
