TEXT: CARGLASS / PHOTOS: DIVERSE ORIGIN, PROVIDED BY CARGLASS
Whenever we get behind the wheel we keep looking through it, but the windshield is still a great unknown to most of the public. Above all, with regard to its contribution to security. In addition to its obvious implications on visibility, the windshield provides up to 30% of the strength of the vehicle structure and it is a key element to prevent the roof from sinking in the event of a rollover.
The effectiveness of the passenger airbag is also conditioned by the good condition of the windshield, since when deployed it rests on it, exerting enormous pressure. And ADAS active safety systems, which inform the lane departure or emergency braking warning system, are based on a multitude of sensors that are usually installed on the windshield.
Since it began to be used in cars at the beginning of the XNUMXth century, the windshield has been the protagonist of many stories and curiosities. In Carglass® Spain we review some of them to better understand this fundamental part of any car.
The first windshields
The drivers of the first cars used to wear glasses to protect themselves from the wind, dust and stones that could jump off the roads. At the beginning of the XNUMXth century, the first front protection glasses began to be introduced. These windshields were composed by two horizontal glass panes movable: when the top half got dirty, the driver could fold it forward.
But soon the windshields they earned a bad name, because in an accident they broke into a thousand pieces and caused injuries to the occupants, pedestrians and motorists; which also began to provoke numerous lawsuits. For this reason, when the first closed cars appeared, with windows on all four sides, many people were afraid to get on.
Henry Ford leads the way
In the 20s, Henry Ford became convinced that it was necessary to make automobile glass - especially the windshield - safer; either because several friends had suffered accidents, because of the lawsuits received or because he did not like that the rear window of the Model T distorted reality. Ford was also concerned about the escalating price of glass, whose manufacturers could not absorb the growing demand from manufacturers.
For these reasons, Ford instructs Clarence Avery, the mechanical "genius" of the company, who seeks a new way of manufacturing that achieves a more resistant and cheaper glass. Together with the specialist Pilkington, they create a new glass manufacturing process that is much more resistant and cheaper, since it is produced in the same Ford River Rouge plant.
Laminated glass, a revolution discovered by chance
The laminated windshield is one of the inventions that has saved the most lives and injuries on the road. And it was discovered by chance in 1903, when the French inventor Edouard Benedictus dropped a glass vase on the ground and did not break into a thousand pieces. The cause? That glass had contained cellulose nitrate and the dry film that remained on the glass held the pieces together when it broke.
In England, John C. Wood makes a similar discovery in parallel, but it is Benedictus who presented in 1909 the patent for two layers of glass with one of cellulose between them. In 1911 he created the Société du Verre Triplex, which manufactured a glass-plastic compound to reduce injuries in car accidents.
Does not fade
Laminated glass was widely used in gas masks during World War I, but it was slow to catch on in the automotive world because of its price and because the middle layer faded over time. The first changed after the 1937 United States Glass Workers' Federation strike.
The latter was solved in 1938, when Carleton Ellis manufactured the polyvinyl butyral. In 1939, an advertisement for Ford said that "Safety glass 'Indestructo' gives the most complete protection. In addition to not breaking into a thousand pieces, it is crystalline and never discolored ”.
A gigantic increase in car safety
It was not until well into the 30s that laminated windshields became popular and became one of the most important safety innovations in automotive history. for many reasons. The first, as we have said, that the glass no longer splinters into a thousand pieces, reducing injuries to the occupants in the event of an accident. The second is that, being more resistant, it prevents passengers from being thrown out of the car in a collision. And the third, which increases the structural rigidity of the car and protects the roof from crushing in the event of a rollover.
Oldsmobile was the first brand to include the windshield as a standard feature in all its vehicles, in 1915. Ford had offered it since 1908 in its Model T, as an option with a $ 100 surcharge (in a package with the speedometer and the headlights), a somewhat high price if we consider that the cheapest version of this model cost 825 ($ 18.000 current). The first standard laminated windshield was assembled by a Rickenbacker in 1926, two years after Lincoln outfitted various police departments with the Police Flyers model, which featured a 2,5cm bulletproof glass and polycarbonate windshield. thick.
The first one-piece windshield with curved shapes used it Chrysler in 1934, in its Airflow Custom Imperial 8 model. Much later came the first panoramic windshield, which boasted the concept car from General Motors LeSabre, introduced in 1951.
In the early 30s, Cadillac and Chevrolet began designing cars with sloped windshields, by design and aerodynamics. In 1936 General Motors definitively introduced the vertically divided windshield in its cars. And there is a patent from those years of the first anti-fog system.
Ford's history with windshields wrote a new chapter with the stunning 2016 Ford GT, the world's first car to feature a glass windscreen 'Gorilla Glass'. Developed for smartphone screens, it is lighter (up to 30%, saving 5 kilos in weight), thinner (25%) and scratch resistant than traditional glass. It is created with many layers: a reinforced interior, a noise-absorbing thermoplastic intermediate, and an annealed outer layer glass.
Carglass® is the leading company in Spain in repair and replacement of vehicle windows of any make, model or age. With a history in Spain of more than 18 years, it has 222 of its own centers and 98 Mobile Workshops with an integrated system to cover the entire national territory. In 2016, the company performed more than 530.000 glass repair or replacement services.
Carglass® Spain is part of the Belron® Group, a world leading company in automotive glass repair and replacement, the only specialist in the sector that offers services internationally with a presence in 34 countries and a workforce of 26.300 people. For more information visit www.carglass.es
* Article prepared by press release