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).
Undesirable features found during tests of a hydraulic steering damper.
| Identifier | WestWitteringFiles\P\October1926-November1926\ Scan054 | |
| Date | 12th October 1926 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} ORIGINAL Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}5/LG12.10.26. x235 x8430 HYDRAULIC STEERING DAMPER. Further tests have shewn up one or two undesir- able features of the hydraulic steering damper. We find that if we get the least lost movement in the damper it ceases to eliminate the small nibbles on the steering wheel which are so objectionable on some 20 HP. cars at 40 m.p.h. and are frequently a source of adverse criticism on the Phantom. This is true whatever load is put on the damper. The result is an unstable steering at high speeds which is heavy on a lock. The axle hydraulic shock dampers which have completed 10,000 miles have developed a very small amount of lost movement due to cumulative wear in the link bearings and in the bushes supporting the lever. We find that even this quantity of lost movement somewhat impairs the function- ing of the damper when used to eliminate steering joggles. Another impression we have formed is that, for a given heaviness of steering on a lock, the hydraulic damper is slightly inferior to friction in suppressing joggles even when the former has no lost movement. We conceive that this may be due to the fact that the co-efficient of friction at rest is greater than the co-efficient of friction in motion. (This can easily be demonstrated by a spring balance on the steering wheel). contd :- | ||