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).
Continued description of a duplicated ignition system's operation, focusing on contact breakers and spark generation.
| Identifier | WestWitteringFiles\N\2October1925-December1925\ Scan118 | |
| Date | 1st November 1925 | |
| Contd. -2- EFC4/T3.11.25. system, if one contact breaker fails by not making contact, the other one does duty. In the ordinary way, the later one to break does duty. In the present system, in addition to duplicating the contact breaker in the Liberty sense, primaries, secondaries and condensers are also duplicated. This does not, however, enable secondary sparks to be obtained from each break independently - the first contact breaker to break will cause no H.T. spark with the arrangement as given (this is assuming all the time that both switches are on), but the current which has built up in the circuit which is then broken, will be instantaneously transferred to the other circuit without appreciable change of flux in the core; and when the other or second contact breaker breaks, the break of the one (total) primary current will induce H.T. currents on both secondaries, which currents will be conveyed away to the sparking plugs, via their respective distributors. In all cases, the duplicate sparks will be produced at the same instant, e.g. the instant of the second break, and nothing will happen at the instant of the first break. This would appear to be still the case, even with the impedance included in the switch to ground connection, because the transference of current from one primary to another does not require a momentary alteration in the total current through the impedance. In fact, it is difficult to say, | ||