From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Investigation into two systems of gear grinding for gearboxes, favouring the Gear Grinding Co. system over the Maag system.
| Identifier | ExFiles\Box 137\5\ scan0067 | |
| Date | 20th February 1922 | |
| Rolls-Royce of America Inc., Springfield, Mass. OY. C. to Hs.{Lord Ernest Hives - Chair} GROUND GEARS FOR GEARBOX. X.4365 X.3426 Referring to OY3/G6.2.22, I investigated two systems of gear grinding - (a) The Maag. (b) A special system of former grinding developed by the Gear Grinding Co., of Birmingham. After investigating the Maag system I turned it down as not being suitable for our requirements, but an examination of the methods and machines used by the Gear Grinding Co., over a year ago satisfied me that the system in question was a thoroughly reasonable manufacturing proposition. The Gear Grinding Co's system was originally an American idea, but as marketed in America, and attempted by the Gear Grinding Co. originally, the system was an absolute failure, owing to the fact that they got good and bad results indifferently under similar conditions. The Gear Grinding Co., however, did not despair of making good, but started about redesigning the system, and eventually they produced a machine which is exceedingly reliable in practice and will turn out gears absolutely interchangeably if required, or they can "mate" gears in pairs. The basic idea of the system is, former grinding, using a 13 or 14" wheel, the wheel being trued up by a special mechanism, working off former involutes, so that the system is a former system and not a generating system of grinding. I discussed the question of producing gears in America upon a similar principle, but they informed me that the owners of the patent over there had never seriously got down to the job, and that so far as they were aware, the American Company from which they originally bought their patent, for England, are in the same position now as the Gear Grinding Co. were before the War, under which conditions they did not seem to consider it of any use referring Rolls-Royce of America Inc., to the original people, as they were afraid they would be disappointed. I examined one of the original American machines and compared it very carefully with the latest type machine developed by the Gear Grinding Co. and satisfied myself that gears produced in the two machines would have very few features in common, the American machine having several obvious faults in connection with same, which had been entirely rectified and overcome in Mr. Orcutts' design, with which the Gear Grinding Co. are at present working. contd:- | ||