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).
Design and reliability of a locked switchbox and ignition system, comparing various options.
| Identifier | ExFiles\Box 4\5\ 05-page264 | |
| Date | 28th March 1924 | |
| To E.{Mr Elliott - Chief Engineer} from R.{Sir Henry Royce} c. CJ. BJ. RG.{Mr Rowledge} WOR.{Arthur Wormald - General Works Manager} DA.{Bernard Day - Chassis Design} HS.{Lord Ernest Hives - Chair} PN.{Mr Northey} EPC. BY.{R.W. Bailey - Chief Engineer} EP.{G. Eric Platford - Chief Quality Engineer} x8790 SECRET. R8/M28.3.24. LEC. 1849. LOCKED SWITCHBOX & EAC. IGNITION X.9730. X.9780. x8790 I wrote to you hurriedly about this. (1) Pointing out the decrease of reliability of two switches in series (for battery ignition). (2) Our difficulty is that we do not exactly know what ignition will ultimately prove best and simplest. (3) We expect double ignition will be needed always on, and accurately synchronised and automatically advanced. (4) Double battery ignition would appear at the moment to be safer, to keep accurately together, with Goshawk type of standby magneto. (5) Supposing this, what does the switch do? How can we test if both in good order while on the road? - Seems difficult. Also large battery ignition current. Therefore go on with 2 entirely separate ignitions as arranged. (6) If we use the 4 position modification, we only need magneto earthing switch anywhere to complete the scheme for single battery and ordinary magneto ignition. We can do everything but run on the magneto only without charging. Position 1st. Off. 2nd. M & B ignition (no charge - no magneto, when desired by extra switch) 3rd. M & B & Charge. 4th. M & Charge (for test and when short of current). This is quite an easy alteration to that arranged. Result - Lock is correct, no additional complications, and maximum reliability. To complete - We want magneto with automatic advance, reliable and accurate, or the RR. scheme of relay advance coupled to both battery and magneto controls for safety. We must work at this latter. R.{Sir Henry Royce} | ||