The anchor escapement is a mechanism in mechanical watches that regulates the release of energy from the mainspring to the gear train, ensuring accurate timekeeping by controlling the movement of the balance wheel.
The anchor escapement (also called the recoil escapement) is a mechanism that regulates energy release from the mainspring to the gear train. Named for its anchor-shaped pallet fork, its pallets engage the escape wheel teeth alternately, controlling the gear train's advance. Invented in the 17th century, it preceded the Swiss lever escapement as the standard in clockmaking and early watchmaking.
The anchor's two pallet faces alternately catch and release escape wheel teeth as the balance wheel oscillates. Each oscillation allows the escape wheel to advance one tooth — releasing controlled energy to keep the balance wheel swinging. The name 'recoil' refers to slight backward motion of the escape wheel when the impulse face engages, which distinguishes it from the deadbeat escapement.
The anchor (recoil) escapement has a slight backward recoil of the escape wheel at each beat, which is inefficient. The Swiss lever escapement, derived from the anchor, uses different pallet geometry and a safety mechanism to eliminate recoil, improving efficiency and accuracy. The lever escapement became the modern standard — anchor escapements are mainly found in antique clocks today.