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).
Valve spring coil vibrations and requesting specific data for a modified spring design.
| Identifier | ExFiles\Box 56\2\ Scan094 | |
| Date | 30th August 1930 | |
| X.290. To By.{R.W. Bailey - Chief Engineer} from EFC. EFCL/AD30.8.30. VALVE SPRING COIL VIBRATIONS. I have gone into the matter of vibration of spring coils and the attached represents the problem as it appears to me. You will see that the problem of increasing the frequency number of the spiral spring, without at the same time increasing the stress for a given deflection, is somewhat involved and therefore indefinite, and that further a mathematical justification for the use of taper spiral springs is somewhat difficult to give definitely. If you consider it would be of any value to you, if you would give me the following particulars of an existing spring which is liable to give breakage trouble, I would attempt to arrive at the modification of this spring which, so far as I could tell from the principles given, might be expected to be superior to the existing one. The required particulars would be as follows :- Diameter of wire. Mean diameter of coil. Number of effective turns. Free length of spring. Set up length of spring. Fully compressed length of spring. The load on the spring in the set up position is on principle contained in the above data but mention of its amount would probably be of value. EFC. | ||