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).
Diagram of a push-button switch showing movement radii and a method for testing carbon gap clearance.
| Identifier | ExFiles\Box 34\3\ Scan039 | |
| Date | 27th August 1919 guessed | |
| Diagram of Push Button Switch showing radii of movement of Carbon & copper contact & push button. 45 mm radius 30 mm rad > < 23 mm rad > push button copper Carbons. Method of testing Switch for carbon gap clearance when "off". -Micrometer- Resistance Battery. Amps. Switch Flat headed Thimble over press button X X Smooth surface jig. soft packing piece metal packing piece Set screws on centre line XX Shown here for convenience jig. | ||