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).
Failures and proposing design changes for the battery ignition contact breaker lever.
| Identifier | WestWitteringFiles\W\September1931-November1931\ Scan019 | |
| Date | 28th September 1931 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Wst. c. Sg.{Arthur F. Sidgreaves - MD} c. Wor.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} By.{R.W. Bailey - Chief Engineer} ORIGINAL Hs{Lord Ernest Hives - Chair}/Wst.1/AD28.9.31. X6118. SEIZURE OF BATTERY IGNITION CONTACT BREAKER LEVER We have had a number of cases brought to our notice where the contact breaker lever on our standard battery ignition has seized on the steel pivot pin. On the 20/25 HP. this would mean a complete failure of the ignition, and when seizure has occurred it has been impossible to withdraw the lever without practically scrapping it. A short time ago Ry. instructed that the bush in the lever should be made in brass instead of phosphor bronze with a view to lessening the possibility of failure with as little alteration to design as possible, but we have now had a failure reported on 19-GIV in France which had a brass bush fitted. We suggest that the pivot pin be made hollow and filled with oil soaked wick like the pivot pins on the contact breakers of B.T.H. aero magnetos. Two small holes could then be drilled in the side to allow oil to percolate sufficiently to lubricate the pivot bearing. An alternative is to make our lever insulated, like other proprietory makers, with a bakelite bush working on a metal pivot pin. The screw point would then be earthed. The lubrication of this contact lever bearing is important in view of the higher speeds the breaker will possibly run in the future. Hs{Lord Ernest Hives - Chair}/Wst. | ||