Leonardo da Vinci's lifting mechanism was a screw jack, a device that raises heavy loads through the mechanical advantage of a screw.
A screw jack converts rotary motion into slow vertical movement. Turning the handle rotates the threaded screw, and the threads push the load upward. Because a small movement of the handle produces a smaller upward movement, the operator can lift a heavy object with less force than direct lifting would require.
Leonardo studied screw mechanisms in detail and drew lifting devices that combined a screw with a drum or other parts. Such machines could have been useful in construction, workshops, and military engineering. The drawings belong to his broader investigations of force, motion, and machines rather than to one confirmed commercial product.
A screw jack is not the same as a simple pulley. A pulley primarily changes the direction of a force or distributes it through a rope system, while a screw jack provides lifting through threaded contact. Modern vehicle jacks still use screw mechanisms, although hydraulic jacks are also common.