(music)
As long as there have been cars with windscreens, there have been a need to clear them from rain.
Many early cars did without wipers altogether, but designs had been patented as early as
1896 as people saw them useful not just for automobiles but steam trains as well.
But as we moved into the 20th century and the automobile craze took hold, more and more
people saw a need for wipers, and many different methods were patented.
One of the first practical wipers for vehicles was patented by Mary Anderson in 1903.
She came up with the idea while on a streetcar in inclement weather.
The screen was designed for bad weather – part of it could be opened so the driver could
reach out and clean it.
But as you can imagine, that didn’t work too well!
She designed a rubber wiper with a wooden, spring-loaded arm that could be operated using
a lever from the inside.
Mary tried selling the design but didn’t get much success.
But this was the early days of automobiles, and it would soon become clear that this product
was of immense value.
A big move forward in wiper design and adoption would come from John Oishei.
In 1916 he was driving an early car in a heavy rainstorm and a cyclist ran into him.
Oishei never saw him coming and vowed to make sure this couldn’t happen again.
He founded the Trico Products Corporation in 1917 and he marketed John Jepton’s rubber
wiper blade as the “Rain Rubber” product to fit into the slot present in many car windscreens
of the day to allow the windscreen to be manually cleaned.
It’s frightening to think of trying to operate manual wipers on these early cars!
After the First World War, sales of motor vehicles took off, and Trico’s sales boomed,
moving into ever expanding buildings in Buffalo, NY – a city that knows all about bad weather!
They soon improved the wiper, adding the spring that holds it onto the glass.
Trico still exists today and is one of the top wiper blade manufacturers.
But drivers needed an automatic windscreen wiper.
An early system using rollers was developed in 1917, but an improved system using wipers
appeared in 1921.
Instead of electrical power, early systems used exhaust air from the engine, but this
had the unfortunate side effect of linking the wiper speed to the engine speed.
Trico would purchase the company that produced it and vacuum-powered wipers would be sold
until the 1960s, but it was clear that these were inferior to electrically powered versions
that slowly started to take over.
To save money, early Citroën 2CV wipers were mechanically powered from the engine, but
like the exhaust system they would speed up as the car’s speed increased.
When the car wasn’t moving the wipers stopped, making forward visibility tricky.
Citroën thought of this and added a handle under the steering wheel to allow them to
be moved by hand!
The earliest wash-wipe feature appeared in 1936, but gained widespread adoption in the
1950s when a press of the windscreen washer button would squirt some washer fluid and
automatically operate the wipers for only two or three times.
Also in the 1950s many cars would switch to the now familiar parallel wiping system to
cover a larger surface area of the screen.
Modern two-wiper systems use a clever lever mechanism to convert a rotating motion of
one motor into the complicated dual windscreen wiper action you see on your windscreen.
With different length lever arms, each wiper has a different motion and stop point.
Various forms of intermittent wipers were invented, starting in 1923, but it was serial
inventor Robert Kearns’ 1963 design that was the first truly practical solution.
Wipers up until then generally had two speeds – slow and fast.
While driving in light rain he kept switching between low and off and getting increasingly frustrated.
It was then he hit upon the idea of the wipers “blinking” like the human eye did, wiping
only once every few seconds.
His solution was to use a capacitor to store up electrical current, releasing it only when
the capacitor was full.
But there was much more to mastering the system.
Every time it rained, Robert would rush out to the car to test his system.
After much tweaking he had a system that could not only vary the period between wipes, but
also the wipe speed.
He’d also managed to make them adjust based on the amount of water on the windscreen.
After all this time, he offered his invention to Ford who seemed interested, despite claiming
to be working on a solution themselves.
What Ford actually had was a 1961 system from Trico that had some serious deficiencies.
It was also expensive, with 29 individual parts, where Robert Kearns’ only had 4.
Ford were interested and asked Kearns to put it through reliability tests to prove it was
a system that would work for customers day in, day out.
It took over 12 months, but by November 1964 he’d proven the system was reliable and
soon had the solution patented.
After further demonstrations, Ford agreed to use his product on the 1969 Mercury line.
As part of this agreement, Robert was asked to tell Ford how his product worked, purely
for safety reasons of course!
5 months later, he was told Ford no longer wanted his product as they’d produced their own solution.
The deal was off.
When Kearns took one of Ford’s wiper mechanisms apart, he found they’d copied his design
and called it their own.
Soon other car companies in the US and around the world were using the same system.
To say Robert Kearns was incensed would be an understatement.
Where once he was consumed with a desire to invent, he was now filled with an all-consuming
rage, primarily aimed at Ford and he was going to have justice.
He filed a lawsuit against Ford for patent infringement.
Ford took a dim view to patents in general.
When Henry Ford started in 1903, all US automakers were paying royalties to a patent lawyer who’d
patented the basic automobile design in 1879 even though he’d never actually built one,
and was waiting for a day when others would make it practical so he could claim the royalties.
Ford had been the first automaker to take on this patent monopoly and win, and he was
praised for it.
Ford believed all new inventions are built upon discoveries of thousands of people since
the dawn of time, and to prevent their free use killed free competition.
When you’re going up against a big company like Ford in the 1970s, you need to have deep
pockets and a strong desire to succeed.
Kearns didn’t have deep pockets, but he drafted his family in to mount a legal challenge
they crafted themselves, all to seek recompense for his perceived injustice in Ford’s theft
of his product.
The strain of Ford’s legal manoeuvres to delay or kill the lawsuit weighed heavily
on Kearns, and his yelling and shouting was too much for his marriage.
Ford offered to pay him off to make it all go away, but by now it wasn’t about the
money, Robert wanted justice.
It took 12 years, but in 1990 Kearns’ lawsuit came to trial.
The court found in Robert’s favour and awarded him $10.2M (£8.1M, €9M, $14.6M AUD), despite
the fact the increasingly distraught Kearns had abandoned the courtroom two weeks earlier
to go camping to escape the madness.
But for Robert, the Ford case wasn’t the end.
He wanted justice from all car makers who had infringed his patent.
Chrysler was next on Kearns' hitlist in 1992, handing over even more than Ford.
Robert Kearns' story was the subject of the 2008 film “Flash of Genius”, and it’s
based on a New Yorker article that’s well worth a read that I’ve linked to in the description.
Although Kearns' design had a form of rain-sensing, Citroën introduced a more advanced version
on their 1970 Citroën SM.
If the windscreen was relatively dry, the wiper motor drew high current, which would
set the control circuit timer to a long delay for the next wipe.
If the motor drew little current, it indicated that the glass was still wet, and would set
the timer to minimise the delay.
More modern systems use the principle of total internal reflection, which allows them to
sense rain even when the wipers are turned off.
An infrared light shines at 45° onto the glass.
If the glass is dry, the refraction angle is 42° and most light is reflected.
If the glass is wet, the refraction angle becomes wider which means much less light is reflected.
By using a sensor to detect the amount of infrared light, the car can turn the wipers
on an off automatically.
Looking for a more accurate system, or to save on parts, companies such as Tesla have
used their onboard cameras along with image processing software to determine how much
rain is on the windscreen.
So far, at least in my experience, it doesn’t work very well.
Some systems got rid of the notion of wipers all together.
A clear view screen is a round piece of glass that spins to remove fluid with centrifugal force.
From the 1930s it was used on ships, but it’s also been used on public transport and enclosed machine tools.
Mechanical solutions like this can be improved with water-repelling glass treatments like
Rain-X, which is also used on regular car windscreens to help improve visibility when it’s raining.
A big thank you to all my Patrons for supporting me.
To get early advert-free access to new videos, or to appear in the credits please consider
supporting me using the Patreon link below from just $1 or 80p a month and hit that subscribe
button to get notified of new videos.
Thanks for watching and see you in the next video!