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).
Comparison of sleeve and rotating armature magneto performance, referencing the 20 HP, 40/50 HP, and E06 models.
| Identifier | WestWitteringFiles\Q\February1927-March1927\ 84 | |
| Date | 8th March 1927 guessed | |
| -2- Contd. there is less unwanted energy than in the case of the rotating armature machine where we must have a good deal of unwanted energy at the high speeds in order to obtain a good slow speed performance. As in the 20 HP. case the magneto has to be run in connection with the battery ignition distributor, it should have in order to save the distributor points, more of the characteristics of the battery ignition system, or at any rate as regards slow and moderate speeds, and to us it appears that this is more particularly the case with the sleeve machine when the sleeve is properly used than with an ordinary rotating armature machine. With the sleeve a distinctly better performance at slow speeds in the retarded position than in the advanced can be obtained. But it should be arranged that in the retarded position of the magneto the sleeve should be nearly in the maximum position from the point of view of flux. We have pointed out to Messrs. Norths that this has not been the case for E06. magnetos nor in the ROL., and had it not been for the desirability of changing the 40/50 HP. magneto to a non-sleeve type for other reasons, we should probably have conducted some experiments on the E06 magneto to improve the internal time functioning of this machine by making better use of the sleeve, for which we have special cams in readiness, thus obtaining, we consider, still better low speed sparking in the retarded position. Contd. | ||