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).
Technical update on gearbox designs for the 25HP and 45HP car models, detailing the synchro-mesh and a new friction-operated unit.
| Identifier | ExFiles\Box 104\4\ scan0025 | |
| Date | 12th June 1931 | |
| SG.{Arthur F. Sidgreaves - MD} FROM R.{Sir Henry Royce} X5310 R3/M12.6.31. C. to WOR.{Arthur Wormald - General Works Manager} HS.{Lord Ernest Hives - Chair} C. to RHC.{R. H. Coverley - Production Engineer} BY.{R.W. Bailey - Chief Engineer} CAR WORK - GEARBOXES. X.5310. X.7310. 25HP. The synchro mesh design is now complete at WW. 45HP. The double top design is now nearly completed as a friction operated unit - i.e. deleting entirely the jaw clutches and the control is by fluid pressure which can be from either the engine oil or gearbox oil pump: so far we have chosen the latter. The electrical control involved us in too many parts and has been abandoned. With this scheme we do not touch clutch or accelerator, or side lever. It should give increased acceleration and higher maximum speed, and less torque reaction vibration and overspeed engine vibration, and less consumption of fuel and oil, but naturally only to 5 or 10% - i.e. one must not expect too much. The parts have been schemed and designed to go in the present box. If successful we should completely redesign simpler and lighter, and only use a 2 speed gearbox which is very definitely smaller, lighter, and cheaper, than the 3 speed at present fitted which is nearly a 4 speed. R.{Sir Henry Royce} | ||