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).
Ongoing clutch development issues, including problems with pressure plates, splines, and cross binding.
| Identifier | ExFiles\Box 13\7\ 07-page063 | |
| Date | 11th October 1931 | |
| -2- Hs.{Lord Ernest Hives - Chair}/11.10.2.31. Contd. We are still not free from troubles with the clutch having the Ferodo rivetted to the driven member. Because of this we are going ahead with a further batch of 50 cars with the present standard clutch plus the improvements. It will be remembered that on the 10,000 miles test the cast iron pressure ring cracked. This has since been strengthened up. We found after that, we got into trouble if the clutch was slipped to any extent due to the pressure plate becoming jammed which made it so that the car could not be driven. This was found to be due to the expansion of the pressure plate causing it to bind on the splines. We have since doubled the clearance and have overcome this trouble. We are still, however, not entirely satisfied with it. It would appear that with the extra clearance on the splines we now occasionally get cross binding. The point of interest is that we have been able to improve the life of our present clutch so much that the advantages in the new one are considerably reduced. We are making further tests and will report later. Hs.{Lord Ernest Hives - Chair} | ||