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).
Page detailing proposed experiments and rig tests to address crankshaft and flywheel vibration issues.
| Identifier | ExFiles\Box 137\4\ scan0089 | |
| Date | 10th September 1930 guessed | |
| -2- (8) To try effect of crankcase stiffness we can run the engine without the last main bearing. However, we shall have to locate the crankshaft endwise on one of the other bearings. Also we shall have to retain the oil in the crankshaft at the last journal. Also we might try effects of large and small amounts of end play on the flywheel vibration. (9) Try a flywheel with the back plate skimmed down very thin, say to .062" thick. (10) Try a roller bearing on the clutch spigot at the back of the flywheel. The spigot may require stiffening. (11) Try a flywheel with less overhanging weight, and a stiffer back plate, i.e. with more metal in plate and less in rim. Measure various M.{Mr Moon / Mr Moore} of I.'s before running. General. While doing rig experiments on this subject, we should also like to investigate the possibilities of a damped spring drive between crankshaft and flywheel, as used to cure C.T.V. on the 6 cyl. AC, Austro-Daimler 6 cyl., and a recent model 8 cyl. 5 litre Bugatti. It is possible that we might find some way of mounting the flywheel between two bearings of its own, and driven flexibly from the crankshaft, which would overcome both the trouble of crankshaft torsional vibration and flywheel vibration. Our car torsional periods occur at approx. 95 m.p.h. in both cars, at present; it is not so important in the 20 h.p., therefore, but fairly important on the Phantom. The effect of subh a spring drive on torque reaction vibrations would also be of interest, and we might find it enabled us to use a light flywheel again with no side-shaft rattles. Another test we should like to do on this rig where we can motor the engine, is to try and measure the increase in stroke measureable at T.D.C. (if any) at high speeds, i.e. have a small aluminium rivet mounted to just touch the piston top (numbers 3 or 4 for preference) at low speeds. This should be held fairly tightly in a clamp. Then we would run the engine up and see if this rivet was pushed any further up by the piston cont'd.{John DeLooze - Company Secretary} | ||