What type of clock mechanism did Leonardo da Vinci improve with weights and escapement studies?

Leonardo da Vinci studied and improved designs for mechanical clocks.

His notebooks contain drawings of gears, weights, toothed wheels, pendulums or balance-like regulators, and escapement mechanisms. These studies show him investigating how controlled periodic motion could regulate the release of energy from a weight. Accurate timekeeping was a major mechanical challenge because friction, manufacturing limits, and irregular motion affected clock performance.

Leonardo did not invent the mechanical clock, which had developed in Europe centuries earlier. His work belongs to the Renaissance tradition of analyzing and refining existing mechanisms. It is also important not to attribute the pendulum clock to him: accurate pendulum regulation was developed later, especially through seventeenth-century work associated with Christiaan Huygens.