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).
Technical report discussing issues and proposed improvements for a clutch system, focusing on squeaks, life, stopping, and bearings.
| Identifier | ExFiles\Box 85\2\ scan0294 | |
| Date | 16th November 1936 | |
| -5- Rm{William Robotham - Chief Engineer}/Smth.39/AP.16.11.36. pedal load at medium and high speeds. 3. Squeaks. The only driven plate with which squeaks are likely to be a problem is the R.R. one and we have had no definite evidence that they will trouble us with this. 35-MX.{John H Maddocks - Chief Proving Officer} squeaked at first but has now improved. 36, 37 & 37 EX. have similar plates and give no trouble. We propose to try cementing the facings to the plate so as to make a solid construction. A plate with a flexible centre is also being made and should help squeaks. 4. Life The durability of the clutch will be greatly increased if we are able to standardise VM.20. Ventilation will also increase life. A scheme for applying ventilation to the present clutch has just been issued. The flexible flywheel arrgt. and the new clutch will have ventilation. 5. Non Stopping. This occurs mostly when the clutch is hot. The Oilite bush is the trouble, becoming tacky and dragging the clutch shaft round with the clutch. The driven plate rocks .015 on its splines, measured at periphery. Thus if cushioning and run out plus .015 is less than the actual separation, there should be no drag from the driven plate. Rm.{William Robotham - Chief Engineer}159 throws away oillite bush and carries the trunnion on a stationary sleeve. The tail bearing thus tends to stop the clutch, not make it drag. This scheme is cheaper and works alright, but the Synchro-mesh feels heavier when changing down owing to the braking effect on the driven plate. The scheme is being incorporated in the flexible flywheel and the new clutch. We have tried drilling oil holes in the oillite bush, but with very little improvement. 6. Noisy Trunnion Bearing. At present the trunnion bearing is always rotating. With Rm.{William Robotham - Chief Engineer}169 it only turns when the clutch is being disengaged and should last longer. Summary There are improvements which could be applied to the clutch at short notice, namely:- | ||