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).
Design of gearbox sliding pinions, comparing spiral keys to splines with modified driving angles.
Identifier | ExFiles\Box 6\4\ 04-page115 | |
Date | 19th April 1925 | |
AJS. } E.{Mr Elliott - Chief Engineer} } FROM R.{Sir Henry Royce} Hs.{Lord Ernest Hives - Chair} } c. to CJ. RG.{Mr Rowledge} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} X5310 R2/M19.4.25. GEARBOXES. A.5310 X.5310 My telegram of a few days ago required some further comments to make it thoroughly clear. It seems that we shall not be entirely satisfied with these smaller sliding pinions until they are quite still on the shaft running under a steady load. Spiral keys and teeth were considered by me but were abandoned because the gears would still move about and they would either have back lash, or would come out on over-run. So I prefer to persevere with splines which are parallel with different driving angles. Heretofore they have been practically normal - i.e. from 2º to 15º. My instructions increased this 15º to 30º and 50º for the square shaft with corners removed, and 60º. SEE ORIGINAL FOR SKETCHES+ There is little doubt that all of these will be quite free when the torque is removed, especially if relieved. This will make the thick oil drag less. SKETCH. It will be necessary to still use the torsionally free pinion so that all the bind is under the teeth, and balanced and deflection less affected by shaft. I cannot see any alters objection to the square or hexagon shaft but we could also use acme teeth of the same driving angles. We ought to make 40/50 so that this also has no tendency to move. R.{Sir Henry Royce} | ||