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).
The potential testing of miniature 10mm sparking plugs for cylinder design.
| Identifier | ExFiles\Box 58\2\ Scan089 | |
| Date | 23th April 1934 | |
| Rm{William Robotham - Chief Engineer} 8182b To Hs.{Lord Ernest Hives - Chair} from E.{Mr Elliott - Chief Engineer} E.1/HP.23.4.34. c. Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} Rg{Mr Rowledge}/Rbr.{Mr Rubbra} re Miniature Sparking Plugs. No doubt you have seen the article on 10 m/m sparking plugs in Automotive Industries of April 7th and the data submitted showing the behaviour of this plug compared with the 14 m/m size as regards temperature variation with time. We should like to have some of these plugs for test either from A.C. or our usual suppliers because a still smaller plug, if it can be shown to be practical, is going to help us on cylinder design. It is remembered that at the time when the miniature plug was first introduced there were a number of smaller sizes 12 m/m possibly which were tested but that the manufacturers finally went to press with the 14 m/m size. We do not think however this should stand in the light of further development. The 10 m/m Y.4. A.C. plug is said to have the same length of insulator in the combustion chamber as the 14 m/m K.4. E.{Mr Elliott - Chief Engineer} | ||