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 of rear springs, condemning the split leaf concept and suggesting a return to older practices.
| Identifier | ExFiles\Box 80\2\ scan0124 | |
| Date | 21th April 1920 | |
| R.R. 235 a 100 T S.F. 846. 6 8-19 G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2460. X.2628.b To CJ. from R.{Sir Henry Royce} Copy to Wor.{Arthur Wormald - General Works Manager} " " Oy. " " Bn.{W.O. Bentley / Mr Barrington} " " Hs.{Lord Ernest Hives - Chair} " " EP.{G. Eric Platford - Chief Quality Engineer} RE REAR SPRINGS - CJ/JS{Mr Johnson's Secretary}5/D20.4.20. X.2628 X.1295 I was surprised that considering the time these springs were about previous to starting manufacture, they had not been run in a 10,000 miles test. They appear quite correct in the instructions (technically) except that the split leaf introduces a weakness as well as a flexibility, which is undesirable. They seem quite strong enough for service in England, but the service on the Continent appears to condemn the idea of splitting. The rest of the spring is quite satisfactory in design if properly constructed, as we believe the first ones were probably by ourselves but since the spring makers are more used to making springs which are tapered on the ends of the shorter leaves, we have considered that it would be wiser to go back to this practice, instead of adopting the practice of sheared ends, which is used in locomotive work, and also used for many years in the Lanchester cars. There is no reason that the sheared ends should give trouble. They were easier to make correctly as the curvature of the plate was constant. The fact that the leaves are thicker, was put in to save weight and friction, because the rear springs, if built of the earlier thicknesses, are not stressed so highly as the front springs, and these springs should not have been unsuccessful but for the idea of splitting the top leaf, which evidently leaves it too flexible and weak. Contd. | ||