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 actuation gear, servo, and speedometer drive for the Wraith II gearbox, comparing it to Phantom models and specifying ratios.
| Identifier | ExFiles\Box 8\11\ 11-page028 | |
| Date | 29th June 1936 | |
| r1044 628 HY.{Tom Haldenby - Plant Engineer} C. E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} Hs.{Lord Ernest Hives - Chair} RHo. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} E/IDY.3/HP.29.6.36. Wraith II Gearbox. Actuation Gear, Servo and Speedometer Drive. We send herewith N.Sch.4840 which shows the above and some sections of the casing. The actuation follows that of the Phantom III, such alterations as there are being mainly due to the change lever being at the back of the boxand to the use of a fork instead of a rocking shaft for the reverse gear. The selector rod plungers are placed inside the box on the centre division as was done on Phantom II. The servo drive ratio is 2/21. The speedometer gears are 21/8 giving with tyres of 14.6" effective radius 800 revs per mile. The Wraith and Bentley with an axle of 4.1 and tyres of 14.150" rad will have 782 revs per mile. A trough is provided to feed oil into the rear extension and a return hole is so placed in the diaphragm that the oil level in the extension is high enough to feed oil into the 2nd motion shaft for the lubrication of the 2nd speed pinion. E/IDY. | ||