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).
Reducing servo gear noise by allowing torsional movement on the serrations.
| Identifier | WestWitteringFiles\L\July1924-September1924\ Scan1 | |
| Date | 1st September 1924 | |
| R.R. 493A (20H) (D.A. 652 20-2-34) J.H.D. ORIGINAL EXPERIMENTAL REPORT. Expl. No. 9910 REF: Hs{Lord Ernest Hives - Chair}5/1,029.9.24. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} 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 EP.{G. Eric Platford - Chief Quality Engineer} Wor.{Arthur Wormald - General Works Manager}✓ SERVO GEAR NOISE. √9910 We have proved on several cars that we can reduce the volume of noise coming from the servo gears very considerably if we allow the spur gear to have a slight amount of torsional movement on the serrations. It has been proved that several production cars which had comparatively quiet servo gears, the larger gear wheel was found to be slightly slack on the serrations. The results are not always consistent. We believe this is due to the amount of variation in the amount of friction combined with the slack. We have previously tried slack worm wheels and slack in the teeth of the spur gears, but we have not found this to be any improvement. With the larger gear wheel slack on the serrations, we do not entirely eliminate the noise, but the amount is less than on 46-PK car which you have at W.W. Hs.{Lord Ernest Hives - Chair} | ||