What machine did Leonardo da Vinci design to wind silk thread automatically?

Leonardo da Vinci designed an automatic bobbin winder to wind silk thread automatically.

The machine was intended to place thread neatly onto a bobbin with less manual labor. Leonardo’s drawings show a system of gears and guides that could coordinate the rotation of the bobbin with the movement of the thread. This reflected his close interest in textile production, an important industry in Renaissance Italy.

The bobbin winder did not spin raw fibers into thread; it handled thread that had already been produced. That distinction separates it from a spinning machine. It also predates famous industrial machines such as James Hargreaves’s spinning jenny, patented in the eighteenth century. Leonardo’s design illustrates how he applied mechanical timing and controlled motion to everyday manufacturing. As with many of his inventions, the surviving drawing provides evidence of the concept, but not of a mass-produced machine operating in a Renaissance workshop.