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).
Error with a new stronger servo spring (G.74778) and requesting a return to the old standard spring (G.72484).
| Identifier | ExFiles\Box 67\1\ scan0062 | |
| Date | 12th April 1927 | |
| To BY.{R.W. Bailey - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/AJL. +8370 Hs{Lord Ernest Hives - Chair}/AJL1/LG12.4.27. 40/50 HP. SERVO. Y5370 We find that a stronger spring G.74778 separating the servo friction plates, has been standardised in error in conjunction with the flat star spring to eliminate servo jaggers. The stronger spring is shewn and was called for on N.sch.2192 but had been found to be a definite disadvantage, allowing the rear brakes to be pulled on before the servo plates are closed up, the result being that smooth brake operation is entirely lost. The standardisation sheet mentioned the star spring flexibility only whereas we find that the stronger servo spring has also been included. The alteration is due to come on production on D2. series chassis; would you please arrange that the old standard spring G.72484 is retained and that the drawings are altered accordingly. A similar error occurred on the 20 HP. servo. Hs{Lord Ernest Hives - Chair}/A.J.Lidsey | ||