As a tribute to International Women's Day celebrated every year on 8 March, we would like to share with you the fascinating story of a ground-breaking invention made by women:
Nowadays, we take being able to drive in the rain for granted. But it wasn't always that way - and you have two women to thank for that.
Back in winter 1903, Mary
Anderson was visiting New York City. She noticed that drivers were having to keep
their windscreens down to stop the snow and ice blocking their view. When Mary
returned to her home in Alabama, she hired a designer and invented a windscreen
wiper system in which a spring-loaded arm was controlled by a manual lever to
move across the windscreen.
Figure 1 – Mary Anderson
Mary received a patent for her invention in 1903, but none of the car manufacturers thought it was practical. Yet once her 17-year patent expired in 1920, cars - perhaps unsurprisingly - began to be equipped with a windscreen wiper design very similar to Mary's.
Figure 2 - Mary Anderson's patent US743801
Around the same time, entrepreneur and automobile enthusiast Charlotte Bridgwood built on Mary's work and patented the electric windscreen cleaner - the first automatic windscreen wiper. Charlotte managed a small manufacturing company in New York City that produced the device, which was powered by the car's engine to move the rubber blade across the windscreen.
Figure 3 – Charlotte Bridgwood
By 1923, these devices had become standard on vehicles. But issues with her patent sadly kept her from claiming full credit for the invention and she missed out on a fortune. It seemed that once again the industry had ignored a woman trying to make waves in a man's world.
Yet there is one saving grace in this story. Charlotte's work inspired her daughter Florence Lawrence to become an inventor herself, and it is thanks to Florence that we have indicators and brake lights.
Figure 4 - Charlotte Bridgwood's Patent US1253929
Rain, ice, snow, sleet and dirt will always make it difficult to see through windscreens, in all kinds of vehicle. And innovative wipers are continually being developed, focusing on new materials, shapes or mechanisms, or automatic activation, sensors, noise reduction or aerodynamic resistance. The graph below shows how new inventions have translated into a steady increase in related patents over the last century.
Figure 5 (click to enlarge) - Patent family publications directed to windscreen wipers
Innovations have even included ultrasonic wiper-less windscreen cleaners - can you find the first patent for them?
Yet it seems that the windscreen wiper - the lifesaving device created by Mary and Charlotte - is still firmly in the driving seat.