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).
Positioning and capacity of ignition condensers and the future adoption of electric starters.
| Identifier | ExFiles\Box 34\1\ Scan008 | |
| Date | 10th July 1917 | |
| Contd. -2- R2/10.7.17. magneto ignition. This will result in the two ignitions being always synchronised which may benefit the running of the engine considerably. Regarding the position of the condenser, I think this should be between the beginning end of the primary winding and the earth contact on the contact maker. This will avoid the rush back of current having to pass through the non-inductive high resistance. Remy appears across the contact breaker as at present. To avoid damaging the platinum on the make and break ( and also to reduce the risk of damage to the platinum points on the ordinary trembler coil) I suggest that the condenser be made larger than is necessary for the greatest length of spark. That is to say, one feels that by gradually increasing the capacity of the condenser, the length of secondary spark would grow to a maximum, then gradually reduce. Now one feels as though this size of condenser is not necessarily the best one for preserving the life of the contact points, which I presume would show less and less sparking as the condenser was increased in capacity. It will be necessary to make the size of the condenser at various speeds, up to an engine speed of 3,000 revolutions, when our 6 point contact maker would be running at 1500 revolutions. We have decided that all chassis after the war will have electric starters, and it would seem that this form of battery ignition would be preferable to the one we are (upside down text at bottom) Contd. H.R. 2352 (2,500 408. 28-4-17) Bin. 2156/1S. | ||