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).
Internal memorandum discussing the design of a 3rd and 4th synchromesh spring loading key and an anti-rattle modification.
| Identifier | ExFiles\Box 136\2\ scan0308 | |
| Date | 12th November 1940 | |
| Handwritten at top: Rm{William Robotham - Chief Engineer}/F.J.H. file Gearboxes Any comments? Rm{William Robotham - Chief Engineer} 1153 Typed text: To Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/HH. c. Ev.{Ivan Evernden - coachwork} Rm{William Robotham - Chief Engineer}/HH.2/SW.12.11.40. 3rd & 4th Synchromesh Spring Loading Key. With reference to memo Ev{Ivan Evernden - coachwork}/Tln.1/JH.26.10.40, we send herewith print of scheme PL.389, on which both the original and the anti-rattle keys are dealt with. It will be seen that additional area of contact is obtained by raising the top face of keys by .031", and there appears to be no reason why it cannot be raised a further .031" should this be desired. The original conditions of loading remain the same. Regarding the anti-rattle key, this does not prevent 3rd speed cone rattling when 4th speed is engaged, and vice versa, because the depressed end comes into contact with the bottom of its groove before the opposite end can engage the cone. A modified key is shown on the scheme, in which the depressed end remains clear of the bottom of the groove, the increased depth of key preventing it from possibly sliding under the cone. Handwritten signature over paragraph 2: Jm{Mr Morley} Handwritten at bottom: Rm.{William Robotham - Chief Engineer} A very good point. If we have to use this anti rattle we should incorporate this. Rm{William Robotham - Chief Engineer}/HH. Ref/P.S.H. Le/do Scheme | ||