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 to Champion Sparking Plug Co. discussing ignition systems and improvements to sparking plugs, including experiments with metallic cores.
| Identifier | ExFiles\Box 162\3\ img201 | |
| Date | 8th May 1940 | |
| elect File copy. 6000 Experimental Dept. Rm{William Robotham - Chief Engineer}/RC.{R. Childs}5/JM.{Mr Morley} 8th May, 1940. Champion Sparking Plug Co., Ltd., Feltham, MIDDLESEX. Your ref., Managing Director RAL/EP{G. Eric Platford - Chief Quality Engineer}/6.5.40. For the attention of Mr.R.A.Lidley. Dear Sir, Thanks very much for your letter and interesting laboratory report. We are interested to know that America has experienced the same kind of trouble, and that it has been overcome by improving the ignition system. We have viewed our ignition with suspicion for some time, but after fitting all the so-called high voltage coils on the market on our experimental cars without any improvement, we have come to the conclusion that our ignition system is second to none. We do, however, agree that in order to cope with petrol economy and large gaps, which apparently have come to stay, a greater safety factor will be required, and we are paying special attention to this point. We do feel, however, that the sparking plug requires the same attention. Our Aero section have been experimenting with metallic cores for the centre electrode, in order to eliminate faults due to inconsistency of the cement used for securing it. In this method, copper or silver is melted down the centre of the insulator and the electrode is welded to the end of the core. The above gives practically 100% thermal contact between the centre electrode assembly and the ceramic insulator, and a decided improvement in performance is obtained. | ||