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).
Design improvements to prevent warping in the 'Goshawk II' clutch plate.
| Identifier | Morton\M21\ img007 | |
| Date | 9th July 1921 | |
| To HS.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} Copy to CJ. " " WOR.{Arthur Wormald - General Works Manager} " " BY.{R.W. Bailey - Chief Engineer} " " DA.{Bernard Day - Chassis Design} ORIGINAL RE "GOSHAWK II" CLUTCH. 4 R2/G7/9/21. X3407 X4244 X.3409 The warping of the plate is quite in accordance with what we anticipated, but we thought there were so many plate clutches which should have this fault that we concluded we should be very timid in not making the venture. I quite agree that the first suggestion would be to rivet the ferodo to a thin steel plate. There are also many other ideas, possibly one of which we think you indicate, namely the use of fabric without steel. This would have to be riveted to a metal plate as far away from the centre as possible. If it is still desirable to use the metal plate as we had arranged it, it might be possible to use Invar metal, which has a co-efficient of expansion, which is negligible. You might also test the plate with four radial slits going a good way down towards the hub and four shallower ones across the heated part of the plate. This is to prevent warping by the outer edge expanding only. In this way it would be able to expand regularly. We do not think the edges of the slot would cut the ferodo if they were carefully rounded. These slots need not be wide. The next idea that struck me was to use curved slots in the lower part of the plate, which would be between the hub and the part rubbed by the ferodo. Such spiral slots have the same idea as the use of curved spokes in a cast iron wheel. The rim could get hot and expand without bulging. So that you have six schemes to try, some of which should shew improvement. In conclusion, you will remember that the 20 H.P. Austin and the DeDion and very many others have single plate clutches (Contd.) R R 6307 (50 L) (2 H & Co) 18-5-21 C 3012 | ||