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 dismantling procedure for the Wraith II gearbox.
| Identifier | ExFiles\Box 8\11\ 11-page035 | |
| Date | 17th July 1936 | |
| 628. To: BY Copy to E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} Hs.{Lord Ernest Hives - Chair} NHC Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} GRY{Shadwell Grylls}- WRAITH II GEARBOX. We send herewith N.Sch:-4862 showing the gearbox extension and rear unit support on the frame. A Silentbloc rubber bush is used and the intention is that this shall take the fore and aft load of the prop eller shaft sliding joint and avoid the need for a rigid stay to the unit. However, it remains to be seen whether this is practicable. The end movement allowed by the bush may be too much for the clutch ac tuation. We cannot say what hardness of rubber will be best, but suggest we commence with the same as is used for the rear gearbox suspension of the PH III. Stops are provided to prevent excessive movement in case of failure of the rubber. The same pieces serve to protect the rubber from oil. When dismantling the gearbox from the car, the silentbloc unit is first removed from the gearbox and the frame brackets, after which the gearbox, can be moved back along the centre line of transmission the 4" necessary to clear the clutch. The front end can now be dropped to clear the crankcase and the whole unit moves forwards out of the cross. There is therefore no need to detach the extension from the box. The clearances in the cross during this operation we show by N.Sch:-4854. The external shape of the flange on the extension has been modified from that shown on N.Sch:-4840. E/Hdy.{William Hardy} | ||