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 report discussing developments in steering and transmission systems.
| Identifier | ExFiles\Box 173\3\ img093 | |
| Date | 4th April 1934 | |
| -8- STEERING. This has been assisted by independent wheel suspension and the full Marles with a two toothed follower is now in general use. The ratios are much lower than we could tolerate in England, being about 20-1. This is necessitated by the engine moving forward and the use of still larger section tyres. In spite of an 85% steering gear efficiency, our only chance of getting away with a 15-1 ratio would seem to lie in our lighter engine and cooling system. With a higher geared steering, road shocks may come into the picture again because "knee action" does not claim complete elimination of this trouble, but the improved steering geometry and altered front end frequency which it brings certainly seem to be an asset. TRANSMISSION. There is a reversion to the single plate clutch, even on the largest units. The spring damped clutch centre is retained on the eight jobs. An overall clutch travel of 6" is accepted on the Phantom size of automobile with a pedal pressure of about 30 lbs. The plain graphite thrust block is used on the new La{L. A. Archer} Salle. The fabric is generally on the driven member. Great care is taken to line up the gearbox and crankcase, machining of the clutch pit facing being carried out by a cutter mounted on the crankshaft, and the operation conducted after the engine has been on unit test. No gearbox development better than the synchro-mesh or fluid flywheel and Wilson box seems to be nearing the production stage other than the Hayes. There is evidence that interest is being revived in the fluid flywheel and epicyclic box over here as a means of simplifying the present synchro-mesh freewheel over-speed gear situation. Helical splines for bottom gear are becoming increasingly popular. Vacuum clutch control is practically dead. The Terraplane gearbox is a good example of the way in which these units have been progressively lightened. | ||