The engineer who revolutionized automotive safety
Many of his inventions are still to be found in cars today
Mercedes-Benz safety levels set new standards in the automotive industry
Béla Barényi, who applied for employment at Daimler-Benz in 1939, became the driving force of safety research with his vision of the safe automobile. The young design engineer explained that the main improvement to future vehicles would have to be in the area of safety, not speed. Dr. Wilhelm Haspel, deputy member of the Daimler-Benz Board of Management at the time, was convinced by the unconventional thinking of Barényi and recruited the 32-year-old engineer.
Barényi, born in Austria-Hungary in 1907, studied mechanical engineering in Vienna and worked for various companies in Austria, Germany and France. In 1929, Barényi was working at Steyr where he met Karl Wilfert, who happened to be the same age as him. Wilfert left his position as head of the Bodywork Repair department at Steyr to work for the Mercedes-Benz subsidiary in Vienna in 1929. In the same year, he was appointed assistant to Chief Engineer Hans Nibel at the Test department in Sindelfingen. In 1933, Wilfert became head of the Test, Special Vehicle Manufacturing and several Assembly departments. When his former colleague from Vienna applied to join Mercedes-Benz six years later, Wilfert supported his job application.
Barényi's first project involved working on a test vehicle with a new type of floor assembly under the leadership of Karl Wilfert. The platform frame built by the design engineers did not just solve the problem of shaking vibrations in the Mercedes-Benz 170 V convertible, it also provided significantly improved protection against side impacts compared with the earlier X-shaped oval tubular frames. The era of passive safety thus began in 1939 in a small hut housing Barényi's workshop at the
Mercedes-Benz plant in Sindelfingen. The Second World War then interrupted all further work.
Terracruiser and Concadoro: Designs for the automotive future
After the war, Barényi worked as an independent engineer and designed a futuristic automobile. He combined his ideas of passive safety with visionary bodywork designs. His concept for the six-seater Terracruiser with a central driver’s seat boasted US-style dimensions along with a variable interior. However, the most significant aspect of this automotive design study was not the rear-mounted engine, but its cellular construction featuring a very strong passenger cell in the centre, which was flexibly connected to deformable crash cells at front and rear – the archetype of the rigid passenger cell with front and rear crumple zones.
The three-seater Concadoro was designed at the same time and had similar characteristics, although in this case Barényi had subscribed to the widely held view that as automobiles became a mass-market phenomenon, the customer would not need or demand more than three seats. In this study, too, the driver was positioned safely in a central seat; Mercedes-Benz came back to this idea in 1991 with the F 100 concept car. The bodywork of the Concadoro had a three-cell design with a swivelling cockpit above the single seat row. Even more than the Terracruiser, the Concadoro provided indications of the way forward for the automobile. Its design already included a steering wheel with a padded boss, a safety steering column and windshield wipers that moved into a recessed position when not in use.
The supporting structure of the centre part reveals ideas that were not implemented until much later in the smart roadster with its open-top Tridion safety cell. On the whole, Barényi's Concadoro bodywork design was much further advanced than the bodies of all of the Mercedes-Benz models of the early post-war period.
The rigid passenger cell and other safety milestones
Following his dismissal in 1946 in accordance with laws in force immediately after the Second World War, Barényi was reinstated by Daimler-Benz in 1948. He used the subsequent months to convert many of his designs into new patents. Named "Ponton" (German for pontoon) because of its profile, the Mercedes-Benz 180 (W 120 series) was a production model that incorporated some of his concepts from as early as 1953. The floor assembly was designed and dimensioned such that it provided improved protection, predominantly in the event of a side impact. The design of the W 120 series was thus a reflection of the ideas that allowed the platform frame first designed in 1939 to be patented in 1943.
Even more decisive for the future of passive safety was Barényi's work on a new bodywork concept with a safety cell, which he derived from the visionary designs he produced in the years after the war. In 1951, Mercedes-Benz was granted a patent for the design principle of a rigid passenger cell enclosed by crumple zones at front and rear. These sections of the body were specially designed to deform in the event of an accident, thus absorbing the kinetic energy of the collision. This in turn would reduce the load on the vehicle occupants.
In 1953, Barényi was transferred to the Development department headed by his old friend Karl Wilfert, himself becoming head of the new Advanced Development department in 1955. This turn of events gave him even more freedom to work on his ideas for the passive safety of Mercedes-Benz automobiles. The W 111 series of 1959, distinguished by its modest fintails, was the first Mercedes-Benz to be equipped with a safety body with crumple zones at front and rear and an extremely rigid passenger cell – features that have since gained acceptance across the industry.
Safety steering system
In the W 111 series, Barényi also introduced his new safety steering wheel for the first time. On early vehicles with a rigid steering column, injuries often occurred when the steering wheel was pushed toward the driver during a frontal impact, potentially impaling the driver. The risk of the steering wheel being pushed backward in this way was particularly high on vehicles with a steering gear located far in front of the front axle. An initial measure to reduce this particular danger was taken with the introduction of a yielding, deformable impact absorber on the steering wheel in 1947. After this first safety steering wheel, Barényi developed the concept of a steering wheel with a generously sized padded boss and a deformable linkage between impact absorber and the end of the steering column which had been relocated toward the front. A patent for this design was awarded in 1954.
The first production car in which this steering system with much improved safety characteristics was incorporated was the 1959 Mercedes-Benz “fintail”, as the W 111 series was widely known. Mercedes-Benz took the next step in 1965 by introducing a patented safety steering system with telescopic steering column to the W 108 series. Despite this, Barényi demanded an even safer steering system. The reason was that the telescopic column could lose its flexibility when subjected to lateral pressure in an accident. In 1963, Barényi patented the "Safety steering shaft for motor vehicles", which was based on a steering column in the form of a corrugated tube. This allowed the steering to give way in several directions in an accident. This complete package was first installed in the 123 series which made its debut in 1976.
The wedge-pin door lock
Another passive safety element is the wedge-pin door lock which was patented in 1958 and introduced one year later. This new type of lock featured two safety catches and prevented the vehicle doors from bursting open or jamming in an accident. Older locks often allowed the doors to burst open, even in relatively harmless collisions. This frequently resulted in driver and passengers being thrown from the vehicle. The introduction of the first safety door lock by Mercedes-Benz reduced this risk. Numerous tests resulted in the award of a patent for a "Locking device, especially for motor vehicle doors” in 1949. However, in the event of a serious accident, particularly a rollover, the doors would still burst open.
The wedge-pin door lock solved the problem. Since this new lock held the doors closed in all circumstances, it ensured the stability of the passenger cell and protected the survival space for driver and passengers. After several drafts, the wedge-pin door lock was patented in July 1958 as a "Pin door lock, especially for motor vehicles”. It was first incorporated in a production car in the Mercedes-Benz W 111 series in 1959.
The fintail model represented a milestone in passive safety because of the interaction of numerous innovations within the vehicle. In addition to a rigid passenger cell, crumple zones at front and rear and the wedge-pin door lock, these included an interior design without any dangerous edges. The W 111 series was thus the world’s first passenger car with integrated safety bodywork.