From an engineering perspective does anyone doubt that the wheel came first?
Wheels with protruding pins or cogs must therefore be one of the oldest examples of an engineered component known to mankind? Almost 5000 years ago the Chinese were using gears in various applications, however one of the first written descriptions of what we would consider to be a gear was by Aristotle, 4th century B.C., who wrote direction of rotation is reversed when one gear wheel drives another gear wheel (Hellenic World encyclopaedia).
If we fast forward to the 19th century we discover that various types of cutting tools were being used to produce the required gear tooth profile onto the gear blank (the gear blank being a disc of material with the correct diameters and thickness of the finished gear). At this point in time the nomenclature surrounding gears was very well established, pitch circle, addendum, dedendum, face and flank are all common phrases that are used to describe the detail elements of a gear.
A major step forward in gear manufacture was made by the German inventor Herman Pfauter, who in 1897 invented a hobbing machine that could cut both spur and helical gears.
In 1975 Pfauter Germany unveiled its first NC (numerical control) hobbing machine at a trade fair in Paris. In 1983 the firm delivered it first CNC (computer numerical controlled) hobbing machine.
At our Sub-contract engineering machine shop based in the East Midlands we have a Pfauter gear hobbing machine, which is a 5 axis CNC machine tool that is capable of cutting gears, both spur and helical, up to 673mm in diameter and weighing up to 500kg. We have an extensive range of hobs and a large amount of tooling to accommodate all manner of configurations. In addition we inspect each manufactured gear using a Rotec single flank machine which can supply reports in a graphical format to allow ease of interpretation.