Switzerland / England · Perrelet-era claims c. 1770s (disputed); Harwood granted Swiss and British patents in the 1920s
Self-Winding (Automatic) Mechanism
Partially verifiedAutomatic winding removed the daily manual-winding requirement and, in Harwood's form, established the architecture (bumper weight, later rotor) refined by Rolex's Perpetual and subsequent full-rotor systems.
Eighteenth-century self-winding pocket watch mechanisms are attributed variously to Perrelet and to Hubert Sarton, whose 1778 Parisian academy description is the most concrete documentary claim; the two attributions have long been debated by horological historians.
The modern bumper-style automatic wristwatch mechanism was developed by John Harwood, who filed for patent protection in the early-to-mid 1920s and licensed production through Swiss manufacturers including Fortis.
Background
The development of self-winding watches began in the 18th century, with the earliest credible evidence attributed to the Swiss watchmaker Abraham-Louis Perrelet in late 1776 or early 1777. Hubert Sarton also designed a rotor mechanism, with a detailed description submitted to the French Academy of Sciences in 1778, while Abraham-Louis Breguet later studied and improved upon Perrelet's designs. John Harwood's later wristwatch design used spring bumpers to limit the swing of the weight to about 180 degrees, creating the 'bumper' automatic. Harwood's watch had no conventional stem winder, so the hands were set by rotating a bezel around the face of the watch.
Written from the encyclopedia entries listed under Sources; each statement was checked against the cited text.
How it works
- The Harwood mechanism uses a pivoting weight that winds the mainspring through a ratchet when moving in a single direction.
- Before the invention of the slipping mainspring, early automatic watches utilized a lever system that locked the weight to prevent over-winding.
- Bumper watches contain springs that limit the weight's oscillation to approximately 180 degrees to promote back and forth movement.
Later history
- John Harwood secured a UK patent for his system in 1923 and subsequently obtained a Swiss patent later that same year.
- Glycine released automatic watches featuring a modular movement in 1930, which contributed to their survival during the global economic depression.
How to verify this yourself
Harwood's patents can be searched in the UK Intellectual Property Office historical patent database and the Swiss Federal Institute of Intellectual Property (IPI) register by inventor name and 1920s filing date; exact numbers are not asserted here pending that search.
Manufacturers known to have used it
- Fortis (Harwood licence)
- Rolex (rotor automatic, developed separately)
- most modern mechanical-watch manufacturers
Photographs
Photographs are illustrative examples of the type, not necessarily the exact object described. Verify details against the source file page.
Sources & references
- Automatic watch, Wikipedia (English), retrieved 2026-10-28 (text CC BY-SA 4.0)
- Cutmore, M., Watches 1850–1980
- NAWCC Bulletin, articles on the history of automatic winding
Where sources disagree, the disagreement is stated rather than resolved silently.