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 and specifications of the Wraith Gearbox.
| Identifier | ExFiles\Box 8\11\ 11-page003 | |
| Date | 27th August 1934 | |
| To BY.{R.W. Bailey - Chief Engineer} from HDY.{William Hardy} HDY.{William Hardy}2/HP.27.8.34. c.c. Wor.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} Hs.{Lord Ernest Hives - Chair} Wa.{Mr Wallis} HNC. FEv. Wraith Gearbox. We send herewith N. Sch.4161 which shows the gears shafts and bearings for this box. The box is in most respects the same as for the SpectreCodename for Phantom III but scaled down .850. The gear ratios excepting reverse are the same as for the SpectreCodename for Phantom III. i.e. .760, .503 and .334. The top gear cone is in one with the 1st motion shaft in order to save length. The proportions of the pieces are more favourable to one piece construction on this box than they were on the Phantom S.M. box and we think that it may now be thought that there is no serious objection to the solid construction. The shafts and bores of most of the gears are to be casehardened and the hardened sleeves for the 2nd and 3rd speeds are deleted. The length of the actuating sleeve for the top and 3rd speeds is increased against cross winding without lengthening the box, by milling slots which accommodate extensions on the sleeve. The actuating sleeve for the 2nd speed is secured against cross winding by the use of extra pins. HDY.{William Hardy} | ||