Who invented the automatic door?

Automatic doors are very often seen nowadays in many different places. Airports, residential areas, banks, hospitals, offices, industrial units or transport are just some of the places where you can go through a door without having to press a button.

Automatic doors are part of daily life for millions of people worldwide. But when did they first come about? Who invented the first automatic door? The answer is a mathematician.

You have to go back to the first century AD and to the region of Roman Egypt. It was here that the mathematician Heron of Alexandria invented the first known automatic door. The writers of the day said that he used heat from fire to pump water from one receptacle to several containers using pressure. Thanks to pulleys and ropes, these containers were able to open the doors to a temple.

This surprised many, and Heron of Alexandria soon applied his door opening technique to other places, such as the entrances to the city.

Despite being well ahead of his time, Heron of Alexandria was unable to set up his system in many more places. His contemporaries and subsequent generations believed that it was easier and more effective to open a door using human strength or pack animals.

It was dozens of centuries later, in 1931, when engineers Roby and Raymond designed the first model of a device that automatically activated the opening of a door. The invention was patented and installed in a restaurant in Connecticut, in the United States. It was welcomed by the waiters of the restaurant, as they could move around with their hands full of dishes and glasses without having to use them to open the door.

Years later, the first automatic sliding door was launched onto the market. A product that, in only a few years time, will have been around for 70 years.