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 detailing improvements in a new Watford magneto ignition system for use on engines.
| Identifier | ExFiles\Box 37\3\ scan 036 | |
| Date | 21th August 1917 | |
| The Controller, Technical Dept; Air. Board Office. Strand. W.C.2. X.3172. August 21st 1917. Dear Sir, X.2753. X.2375. X.3172. X.3173. MAGNETO IGNITION. We wish to record various points which were discussed with Commander Bristow during his visit to our Mr. Royce. X.2375. Commander Bristow brought with him one of the latest Watford magnetos which are to be used on the Rolls-Royce engines. This appears to have many important improvements which we understand are as follows:- 1. Lighter weight of the whole machine. 2. Considerably lighter weight in the contact maker moving arm. 3. Long cams for operating the contact maker, which, with(2) should have great beneficial influence on the length of the life of the platinum points and the need for frequent adjustment of the same. 4. Apparently adequate provision made to prevent distortion of the armature tunnel during clamping of the magneto to its carrying bracket. 5. Improvements in the distributor to reduce the possibility of leakage. Our Mr. Royce did not remember exactly whether it was intended to use a jump spark distributor or a distributor with carbon brush, or metal brush in the distributor - The model shown had carbon brushes but it is thought that a jump spark distributor would give better ignition. We are disposed to think that if a jump spark distributor is used it would have to be considerably modified from the usual pattern and should be fitted with jump spark points which are not liable to oxidize such as a platinum wire system as used on the Rolls-Royce car distributor (battery system) (contd) | ||