What clock component did Leonardo da Vinci study using a balance wheel and spring?

Leonardo da Vinci studied an escapement mechanism using a balance wheel and spring in his clock designs.

An escapement controls the release of energy from a clock’s power source. It allows the gear train to advance in regular steps while sending impulses to the regulating element. Leonardo’s notebooks include designs involving a balance wheel, spring, and toothed components intended to improve the regularity of mechanical timekeeping.

Leonardo did not invent the first mechanical clock. Weight-driven mechanical clocks were already established in Europe, and later clockmakers developed other escapements and regulators. His work belongs to a long process of experimenting with friction, gears, springs, and controlled motion.

The design is often confused with the pendulum clock, but pendulum regulation became important later, especially after Christiaan Huygens introduced a practical pendulum clock in 1656. Leonardo’s proposed regulator was based on a balance wheel and spring rather than a hanging pendulum.