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).
Report page on testing a switch's making and breaking capacity, with suggestions to modify the cam lobes for improved performance.
| Identifier | ExFiles\Box 168a\2\ img141 | |
| Date | 8th March 1934 | |
| -2- Hs{Lord Ernest Hives - Chair}/Wat./3/MA.8.34. Cont'd.{John DeLooze - Company Secretary} When tested for making and breaking capacity, some sparking at the contacts was observed, when breaking a circuit carrying 10 amperes at 14 volts. In view of the extent to which this switch will be used, and the fact that the current taken by gas-filled lamps at the instant of "make" is probably more than the steady current, it is perhaps advisable to make the "break" and "make" more rapid. It is suggested that this could be done by modifying the cam lobes on the toggle mechanism, giving them a sharper crest, and a steeper gradient on the falling side. At the same time the rotating blades would so be arranged, inrelation to their respective contacts, that they would neither make contact or break contact, as the case may be, until the toggle arm had started on the downward gradient of the cam lobe. Hs{Lord Ernest Hives - Chair}/Wat. | ||