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).
Technical memo discussing modifications to ignition timing, governor mechanisms, and firing point diagrams for the Phantom model.
| Identifier | ExFiles\Box 37\1\ scan 307 | |
| Date | 29th May 1928 | |
| (2) It is intended that the differential mechanism regulating the hand advance should be left unaltered. We realise this will not allow us to obtain a full 30° governor advance on the flywheel as the hand control absorbs 8° of the magneto advance, whereas the total movement of this latter on the flywheel is only 38°, leaving 30° for governor plus initial advance. The battery ignition will naturally follow in synchronism. LeC.2242. will modify the firing point diagrams shewn on LeC. 1917. We originally asked for these diagrams to be included in the instruction book but apparently this has not been done. We believe that this information is essential for the purpose of understanding the Phantom ignition arrangements. LeC.2242. also shews the alternative form of spring suggested by Mr Royce in his contemporary memos. This can be used if any difficulty is experienced in springing the existing governor. We shew on it the frames holding the governor weights with straight instead of bent tabs. These tabs engage with lips formed on the governor weights and gashed to the requisite width to engage the tabs. The advantage of this method of construction is that we avoid bending the thick metal of the frames and provide a better surface, thereby beyond the bolt for cramping the frame to the weight. The depth of the gash in the weight would have to be slightly below the clamping surface. E.{Mr Elliott - Chief Engineer} (RECEIVED) 29 MAY 1928 | ||