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).
Summary of chassis suspension design, covering the roles and interaction of tyres, road springs, and hydraulic dampers.
| Identifier | ExFiles\Box 71\2\ scan0143 | |
| Date | 25th April 1926 | |
| To HS.{Lord Ernest Hives - Chair} DA.{Bernard Day - Chassis Design} } from R.{Sir Henry Royce} CY. BY.{R.W. Bailey - Chief Engineer} } Le CanadelHenry Royce's French residence. RL/M25.4.26. X8840 C. BJ. Wor.{Arthur Wormald - General Works Manager} RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} NA.{Mr Nadin} CWB. PN.{Mr Northey} EP.{G. Eric Platford - Chief Quality Engineer} Mr. Fuller CHASSIS SUSPENSION. X.8410. X235 X8840 This is not intended to contain anything very novel, but a summary of the above as I understand it, and if correct, I should like it to be generally appreciated by all concerned. TYRES. Lower pressure cannot do the duty we expect from road springs because their rating is always very high (even with full balloons) and their flexibility cannot be damped as much as desired. But they are absolutely necessary to reduce vibrations from the road generally, and to reduce the direct shocks to the steering and enable the back axle to hold the road, improving the braking and general safety, life of the coachwork, and general comfort of the passengers, and as we have now cured or reduced the high speed wobbles, at least out of the danger zone, there is a distinct balance in favour of their adoption. To cure the high speed wobbles we have the RR. hydraulic dampers and a lighter axle; both these also have other advantages. ROAD SPRINGS. It seems generally agreed that these are of the utmost importance, to be very carefully adapted to the load, and of the greatest practical flexibility. Regarding the rear springs we are in a good position - i.e. ample flexibility, ample clearance, and ample steel, (length), and providing these are correct to the load and our standard, it only remains that they are effectively damped without harshness at low speed. This is best met by hydraulic dampers, preferably RR. but failing these the next best is Lovejoy (which are more suitable for the back axle than the front) so the RR. are needed for the front principally because of the higher speed of vibration. It will be realised that the chief trouble with the rear springs is that the load varies so greatly according to the number of passengers, etc. whereas with the front springs the loading is much more constant; this, and the reason that the passengers are chiefly at the back shews the wisdom of using our available weight, extra flexibility and clearance at the back. Now as the present front springs are asked to do more than in pre-front wheel brake days it seems as though | ||