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).
Investigation into dynamo noises, attributing them to belt vibrations and testing potential solutions.
| Identifier | ExFiles\Box 55\2\ Scan073 | |
| Date | 18th December 1919 | |
| To R. {Sir Henry Royce} from Hs. {Lord Ernest Hives - Chair} c. to CJ. c. to Bn. {W.O. Bentley / Mr Barrington} c. to E. {Mr Elliott - Chief Engineer} c. to Da. {Bernard Day - Chassis Design} c. to EP. {G. Eric Platford - Chief Quality Engineer} X.3.7/35a Hs {Lord Ernest Hives - Chair} 1/LG18.12.19. X.516. - RE DYNAMO NOISES. X.493. X.3772. X.3014. X.3.7/35a It has been proved that practically the whole of the noise and vibration which we get on the present chassis is not due to the dynamo but it is due to the vibrations set up by the Whittle belt. The vibrations are transmitted through the dynamo suspension to the frame and from there to the under-shield which is the real cause of the noise. We find that if we take a car which is very bad for "dynamo noises" and fit to it a Dunlop Rubber Belt instead of a Whittle belt, it is excellent, there is a very small amount of noise left which comes from the commutator and the ball bearings but it is nothing one would object to. We cannot use a Dunlop rubber belt because of the oil which gets on to the dynamo belt and also the fixing on the rubber belt is generally unsatisfactory. We have rpoved that if we get a Whittle belt with a greater number of smaller links, it is a very great improvement. We also find that if we fix a spring to keep the tension on the belt, it is a further improvement, this is no doubt due to the fact that when the length of the belt varies due to the links passing round the pulley, the centres will accomodate themselves. We find these two alterations make a very great improvement. They do not make it quite as good Contd. (ONE HUNDRED AND SIXTY FOUR) A L. DOOLEY & Co. H.M. | ||