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).
Secret memo detailing the causes and potential solutions for over-run vibration in an E.A.C. engine.
| Identifier | ExFiles\Box 25\3\ Scan115 | |
| Date | 9th February 1924 | |
| X634 S E C R E T. To HS.{Lord Ernest Hives - Chair} RG.{Mr Rowledge} } FROM R.{Sir Henry Royce} E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} R2/M9.2.24 E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C. ENGINE. OVER-RUN VIBRATION. X.9550. X.634 The source of this trouble I believe must be the variation of the kinetic energy in the pistons and little ends. This varies the speed of the flywheel. Behind this is a revolving mass comprising servo drum, gearbox wheels, couplings torsionally hanging on the 1.1 shaft which is of a suitable rigidity to make a period at the 40 MPH. Several things are possible to make it less or alter its speed :- (1) Lighten the pistons, etc. Result less noise same speed. (2) Increase the flywheel. ditto. (3) Decrease the inertia of the mass behind the flywheel. Result less noise and higher speed. (4) Increase the rigidity of the shaft mentioned. ditto. (5) Fit friction damping ring or disc near centre of torsionally oscillating mass. Probable cure. R.{Sir Henry Royce} | ||