Sunday, July 6, 2008

WHO INVENTED RADIAL TYRES?



As most educated schoolboys will tell you, the rubber tyre was invented by John Boyd Dunlop late in the nineteenth century (actually 1888). If you press him with the observation that rubber tyres were used before that date he will point out that he is talking about the pneumatic tyre – not solid ones.



He will be surprised when you point out that the pneumatic tyre was actually invented and patented in 1845 by RW Thompson (illustrated) and that his concept was more advanced than that of Dunlop in that, rather than just using a rubber tube filled with air, he packed a number of thin inflated tubes inside a leather cover. Pressures could be varied for different ride conditions and, of course one puncture would not be terminal!
For no obvious reason (except possibly the lack of roads!) these tyres never caught on but solid rubber tyres on everything from bicycles to steam traction engines became the vogue. In 1884 the idea of leaving a hole through the centre of the rubber to give a ‘cushion’ effect was developed but we must wait until December 19th 1888 for the first advertisement for a ‘Dunlop Pneumatic Tyre’ to appear – in the Irish Cyclist. On May 18th 1889 a cyclist using these tyres won a race in Belfast and the pneumatic cycle tyre was on its way.


These tyres had a particular shortcoming as they were stuck to the wheel and thus access to the inner rubber tube in the (common) event of a puncture was tedious but by the end of 1890 CK Welsh had patented the design of a wheel rim and outer cover with an inextensible lip. The fundamental design feature of tyres for virtually all types of wheeled vehicles through to today had arrived.



By now, of course, the motor car was appearing and the first motor vehicle specifically designed for the pneumatic tyre took part in the Paris to Bordeaux (and back) race in 1895. 720 Miles and 22 inner tubes later the Daimler finished ninth from a field of 42. From that event to today the simple tyre has developed in many directions, be it towards a child’s tricycle, a giant earthmover or the ubiquitous motor car, the last category itself ranging from micro runabouts to Formula 1 Grand Prix racers.
Each is a triumph of engineering where numerous component parts of rubbers, fabrics or steel are individually formulated and combined to meet the requirements of the particular user. Whatever the application, these tend to be comfort, puncture-resistance, wear and performance, the last generally being measured as road adhesion in wet and dry conditions, as well as absolute speed certification. In a short article such as this it is impossible even to list technical developments but two important leaps forward merit note. In 1948 Michelin created the radial tyre with its vastly superior grip, whilst in 1972 Dunlop did away with the inner tube on car tyres
Price might also be on your list of requirements but it should be low down. With the average family saloon capable of cruising at well over 100mph (on the right roads) and being held on the road by four patches of rubber, each about the size of the palm of one’s hand, what value do you put on the tyre?

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