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).
Memo discussing gearbox design, tooth proportions, and competitor transmission analysis.
Identifier | ExFiles\Box 173\1\ img337 | |
Date | 9th February 1934 guessed | |
quiet bottom & reverse. They have had no trouble with it. They rather increase the unit loading on the splines (see female splines on the gear backed off) to overcome any tendency of the gear to move. I send you a drawing of the Chrysler box and also details of the functions. The box size will answer Hardy's question as to the centres used and the tooth loading. I asked Neracher what tooth proportions he would use if his sole object was to make a quiet light box. He said 45° helix angle 10 pitch. He does not like fine pitch carburised gears, he says the core becomes so small that the tooth strength is erratic, this sounds reasonable. The 10 pitch 45° helix almost exactly parallels what Packards are doing with such success Trick Transmissions. Chryslers are about to standardise an overspeed epicyclic gear which fits onto the back of the gearbox. I enclose a surprisingly bad arrangement print. I shall try and call on the Warner people and get detail drawings. | ||