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).
The Bentley 111 servo, comparing it to the Wraith III and explaining design choices regarding wear and vibration.
| Identifier | ExFiles\Box 99\3\ scan0177 | |
| Date | 30th September 1937 | |
| 200b. C. Dept. (struck through) E.{Mr Elliott - Chief Engineer} Dept. (struck through) D.{John DeLooze - Company Secretary} Dept. (struck through) RM.{William Robotham - Chief Engineer} RM{William Robotham - Chief Engineer}/CRH (struck through) DA.{Bernard Day - Chassis Design}5/G.30.9.37. 441 BENTLEY 111 - SERVO. Herewith is G.CD.104 shewing the servo cam levers, which have to be different to Wraith 111, to suit the Bentley brake layout. In order to reduce the load on the ball bearings due to the 'on' stops, the latter have been carried out beyond the pull rod jaws. We have not provided a rubber "off" stop, because we are afraid the resulting flexibility will bring up the wear previously experienced due to vibration at high speed. It is thought that the wear experienced on Wraith 111 in France may have been due to the previous defects in the servo, and will not occur when the servo is correctly fitted up. DA.{Bernard Day - Chassis Design} | ||