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).
Letter from Joseph Lucas Ltd. discussing developments in battery ignition systems and quiet running dynamos.
| Identifier | ExFiles\Box 37\1\ scan 156 | |
| Date | 1st July 1927 | |
| F/L JOSEPH LUCAS LTD., PAGE 2. DATE 1.7.27. To E.{Mr Elliott - Chief Engineer} Fowler Clark, Esq., Messrs. Rolls-Royce Ltd., DERBY. favourite is that being a self-contained unit it is inherently more reliable than a system which, on many cars at all events, is liable to be put out of action by a fault which may occur at many points in the wiring system, not necessarily in the ignition wiring alone. However, I do think that there will be a larger field for battery ignition in the future. Perhaps there may be a demand for it for the cheapest class of car, and also a greater demand for dual ignition at the other end of the scale. We are at present doing a fair amount of work on 8 and more cylinder ignition, tying out two and more contact breaker levers operating in parallel with different times of opening and closing, the object of course being to obtain a longer period of make than is practicable with the single contact breaker lever. We are also studying the contact breaker problem, and have so far arrived at very much the same conclusions as you have. As regards the quiet running dynamos, we have so far obtained very little success, if any, by using steel wedges, and the same is true of experiments we have made with a continuous liner of steel between pole shoes and air gap. I presume in both cases that the sudden changes of flux density which occur in the normal machine are in reality not much masked by the means adopted. We are trying out your scheme using a multiple of 4 for the number of slots and commutator parts, but these machines are not yet completed. I am also starting a careful investigation of the precise distribution of flux density under the poles, as I think it is possible that this may get us some information as to the most intelligent manner of tapering the pole tips. I will let you know what progress we make in this matter in due course. With kind regards, Sincerely yours, E.O.Turner. | ||