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).
Performance and design of synchromesh units in gearboxes.
| Identifier | ExFiles\Box 148\5\ scan0418 | |
| Date | 18th August 1938 | |
| By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} c. Da.{Bernard Day - Chassis Design} c. Da{Bernard Day - Chassis Design}/Hdy.{William Hardy} c. RHC.{R. H. Coverley - Production Engineer} Rm{William Robotham - Chief Engineer}/Gry{Shadwell Grylls}10/R.18.8.38. SYNCHROMESH UNITS. With regard to RHC{R. H. Coverley - Production Engineer}/DWB{D. W. Brown}1/LS.16.8.38. suggesting round synchro cams operating in part of a circular slot, we have been able to see at Pickfords a Minx 2nd speed synchro-mesh assembly working on these lines. The Minx box had done 19,000 miles and there was no noticeable wear on the corners of the slot in the bronze outer member. The pin was the same radius as the slot; the two halves of the slot are not, therefore, part of the same circle. If the Design Dept. will give us a drawing of a circular cam for the Wraith gearbox we will fit it on Mx{John H Maddocks - Chief Proving Officer}'s car for endurance mileage. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} [Handwritten] Hdy{William Hardy}/ We also learnt from Pickfords that the 3rd speed inner cone and driving teeth used to be pressed on to the gear, but on occasions slowly worked off jamming the synchro unit. It is now all one piece. The locating washer at the front of the 3rd motion shaft has cracked up in several boxes. | ||