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).
Testing and proposed modifications to the Phantom II damper control system on chassis 22-EX.
| Identifier | ExFiles\Box 151\2\ scan0127 | |
| Date | 28th December 1933 | |
| LES x4698 See me HS {Lord Ernest Hives - Chair} To Sg. {Arthur F. Sidgreaves - MD} ) Wer. ) from E. {Mr Elliott - Chief Engineer} c. Hs. {Lord Ernest Hives - Chair} By. {R.W. Bailey - Chief Engineer} EP. {G. Eric Platford - Chief Quality Engineer} Mx. {John H Maddocks - Chief Proving Officer} U/HSY. re Phantom II Damper Control on 22-EX. I tried 22-EX recently, which is fitted with the damper control representative as regards effect of what we are now issuing as standard on P.II. and on a short run to Duffield and back, made in conjunction with EP. {G. Eric Platford - Chief Quality Engineer} carried out experiments in riding with various degrees of damping. There is no doubt that the demonstration of the results obtained by manipulating the lever at the top of the steering column is very impressive, but the riding on the back seat with maximum control on is so exceedingly objectionable at low speeds that it is questionable, as pointed out by EP {G. Eric Platford - Chief Quality Engineer} , whether it is wise for this condition to be possible, and whether it would not be better to have more governor control. Personally I am in agreement with this view as although the driver should not run on maximum hand control at low speed he may forget at times and be unaware of the discomfort he is inflicting on the occupants of the back seat since he himself would not be affected to anywhere near the same degree. Actually the present proportions of damping have come about largely through the total damping required being much greater than that provided by the original design of governor, and a governor with heavier weights will be necessitated by the modification proposed, but we believe some increase in this direction can be obtained without much difficulty. The present governor gives a damper control pressure of 13 lbs at 80 miles per hour, and with the hand control added this pressure rises to 30 lbs. We should propose to increase the governor if possible to 21 or 22 lbs and the range from this figure to 30 should give ample variation for different body weights. By lifting up the governor curve in this way the amount of increased pressure for hand control can be reduced as shown in the diagram. We think this modification would | ||