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).
Ignition wiring tubes and the effects of static induction.
| Identifier | ExFiles\Box 61b\4\ scan0203 | |
| Date | 25th February 1925 | |
| To R.{Sir Henry Royce} From EFC. c. CJ. Wor.{Arthur Wormald - General Works Manager} c. E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. By.{R.W. Bailey - Chief Engineer} Rg.{Mr Rowledge} X4119 EFC1/T25.2.25. ++ X.4119. IGNITION WIRING TUBES - STATIC INDUCTION EFFECTS. X3714 References of previous reports on this subject are EFC1/AT22.5.19, EFC1/T14.11.19 and EFC4/T24.11.19. The first report mentioned can be looked upon as a preliminary description of the principles of the results that follow. As regards the second report, we are only concerned with the section entitled "Effect of passing cable through iron and copper tubes of similar dimensions". It is there shewn that the capacity effect on the main spark with the insulated copper or iron tube is practically negligible and independent of material. The third report mentioned is of the nature of a summary of the various results, indicating that (1) To minimise the static induction effects on the other wires we require to use an earthed metallic tube, but that (2) To keep the main spark up in sparking voltage, we require to have the tube insulated. (Copies of these reports and extract referred to are attached for his convenience to R's copy, as it is unlikely that he will be able to refer to these at Le CanadelHenry Royce's French residence). The reason for the vacillation between the two desiderata is that we have not always as originally and subsequently had spark generators of sufficient output to cope with the capacity effect of earthing the tube, and had proved, particularly in the earlier 20 HP. days, that the Contd. | ||