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).
Technical drawing with notes on a General Motors Corporation patented spark plug insulator design, later abandoned due to breakage.
| Identifier | ExFiles\Box 147\2\ scan0174 | |
| Date | 24th January 1940 guessed | |
| RM{William Robotham - Chief Engineer} Please File 1 1267 General Motors Corporation. Patent No. 16256. Insulator. Resilient "a" shaped washer held under stress and pressing on to the shoulder of the Plug insulator, thereby making a gas tight joint at "A". This scheme now abandoned due to breakage at the point where the washer is pressed on to the insulator. RM{William Robotham - Chief Engineer}/RC{R. Childs} | ||