Leonardo da Vinci designed a mechanical fan to circulate air in enclosed spaces.
His notebooks contain designs for mechanical devices that could move air through rotating blades or vanes. Such ideas were connected to ventilation, cooling, and the movement of air in rooms or technical environments.
A mechanical fan differs from an air pump because a fan moves air continuously through an open flow, while a pump is designed to force air into a confined space. Leonardo’s sketches often explored mechanisms rather than presenting machines that were mass-produced or tested to modern engineering standards.
Electric fans came centuries later. Leonardo’s contribution belongs to the much older history of using mechanical motion to improve airflow before powered household ventilation existed.