Skip to content
The Encyclopedia of Horology

Detached escapement

Lever escapement

Verified

A pivoted lever with two jewelled pallets locks the escape wheel and transmits impulse to the balance through a fork and impulse pin, leaving the balance detached for most of its arc.

Schematic arrangement

How it is laid out

Escape wheelPallet forkBalance & impulse pin

Outline schematic only, drawn to show the characteristic arrangement of wheel, locking member and oscillator. It is not a dimensioned working drawing and should not be used for setting up or repairing a movement.

Advantages

  • Robust
  • Self-starting
  • Good isochronism
  • Suits mass production

Drawbacks

  • More parts than frictional-rest designs
  • Requires accurate pallet geometry

Attribution and period

Attributed to Thomas Mudge, c. 1754; developed through the nineteenth century

Horological firsts are frequently contested. Where an invention is attributed to a named maker, that attribution is recorded as such rather than treated as settled fact.

Photographs

Chinese movement escapement and jewels
Chinese movement escapement and jewels — Hustvedt, CC BY-SA 3.0. Wikimedia Commons file page
Lever of a Watch Lever Escapement
Lever of a Watch Lever Escapement — Micky Aldridge from Finland, CC BY 2.0. Wikimedia Commons file page

Photographs are matched automatically from freely licensed Wikimedia Commons material. Each caption states the actual subject of the image and credits its author; where a close match for this escapement does not exist, a related mechanism may be shown instead.