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).
Tests to eliminate high-speed steering wobbles using hydraulic damping.
Identifier | ExFiles\Box 28\4\ Scan351 | |
Date | 27th August 1925 | |
R.R. 493A (50m) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. Expl. No. 4457 REF. HS{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}1/LG27.8.25. To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to CJ. BJ. c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} HIGH SPEED STEERING WOBBLES. X1152 We have carried out further tests with hydraulic damping. Houdaille shock absorbers were again used, after being carefully fitted up to ensure fairly consistent performance. For high speed wobble tests with high pressure tyres, we have adopted a standard condition of 40 lbs./sq.in. pressure, each wheel being 1 lb. out of balance at the rim. We consider that if we can eliminate wobbles under these conditions, we shall be able to do so on any customer's car. In our road tests we have used the Chronograph to compare the intensity of wobbles under various car conditions. As a general result of our tests we find that so far the most promising method of eliminating wobbles is to fit hydraulic dampers in place of our standard front shock absorbers. We find that if a really marked improvement is to be obtained by hydraulic damping on the cross steering tube, the steering must suffer adversely in consequence. To affect a complete cure under the conditions previously mentioned, the damping on the cross steering tube has to be so great that shunting can only be accomplished with great physical exertion. On the other hand we have had very good results from the Houdailles used as shock absorbers. The extent to which the riding of the car would be affected by these contd :- | ||