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Pfauter 60th Anniversary Booklet
Based on his patent taken out in 1897 (No. 112082 in class 9a), by 1900 Hermann Pfauter had built the world's first gear hobbing machine - and established his first factory in the German machine-tool town of Chemnitz. Pfauter's machine was, of course, not the first able to produce gears of the correct form, it added to those that used (or were to use) the geometry of gearing to achieve the same aim. Prominent in this field at the turn of the 19th and 20th centuries with their gear planer patents were the Englishman Sam Sunderland, E.R.Fellows of the United States and Max Maag of Germany with a gear-shaper method. Hermann Pfauter was justifiably proud of his new method of generating gears, writing at the time of his patent application, "Taken as a whole the new method must be called perfect in itself, and rendering further developments unnecessary." By the late 1950s, the Company had a range of machines in production that included the best-selling P-Types - with many of these well-built and reliable machines still in wide use today. Of these, the P-1250, one of the largest machines in the range, had the same constructional and functional details as all others - and a study of that model will give the reader a good grasp of how they worked - and of what they were capable. The basic principle of hobbing is simple - two rotating spindles are employed, one holding a blank workpiece and the other the cutter, called a "hob", formed with the shape of the required gear teeth. While, in practice, the detail is more complex - and hobbing machines both complex and heavily built - the great advantage of the process is the relative ease of operation. The process, once set up, is entirely automatic with the workpiece and cutter rotating relative to each other and the feed of cut arranged so that the teeth on the blank are formed, gradually, over many revolutions. Most hobbing machines are capable of producing not just one diameter of gear, but a whole range of sizes, the only necessity being a supply of the right kind of (very expensive) hobs. In addition, several blanks can be "stacked up" on one spindle and a whole batch made in one production run. As a portent of things to come in the way of international takeovers and amalgamations, in 1950 Pfauter agreed with the Fellows Gear Shaper Company of Springfield, Vt. to manufacture, under licence, Pfauter machines in the USA Today, the Pfauter company continues, but in July 1997 was acquired by the American Gleeson Company with the deal including a machine-manufacturing subsidiary, American Pfauter, and a cutting tool-manufacturing subsidiary, Pfauter-Maag Cutting Tools, both located in Loves Park, Illinois. In July 1995, Gleeson had already taken over another German gear company, the Berlin-based Hurth Maschinen und Werkzeuge GmbHthe, a maker of shaving and honing equipment used in cylindrical gear production and finishing. Today the whole group, based in Ludwigsburg, Germany. trades as Gleason-Pfauter Maschinenfabrik GmbH.
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