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).
Suggestion for cheaper Peregrine timing gears using a 45° spiral angle.
| Identifier | ExFiles\Box 136\1\ scan0030 | |
| Date | 30th May 1932 | |
| X411 E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}1/MA.30.5.32. 45° SPIRAL ANGLE FOR ENGINE GEARS. We send you herewith a suggestion for cheaper Peregrine timing gears. We think it would be better to try the coarser pitch gears on this engine than on the 25HP as we are unlikely to make any radical change in the 25 now. The reason we have not suggested exactly 11 pitch is that our Maag grinder cannot do an angle greater than 45°. Therefore with 11 DP we should have to go to a 27 or 30 tooth crank pinion. If you agree to ordering a hub for these gears and also with a 14½° obliquity will you have the figures for the DP etc checked and instruct RHC{R. H. Coverley - Production Engineer} accordingly. The depth of tooth we have taken is 2.250/DP. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||