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).
Battery ignition distributor rotor failures during endurance tests and recommendations for increasing insulation thickness.
| Identifier | ExFiles\Box 54\5\ Scan319 | |
| Date | 20th May 1930 | |
| X5680 Ry. from EFC. {E. Fowler Clarke - Electrical Engineer} EFC {E. Fowler Clarke - Electrical Engineer} 9/AD20.5.30. X.5680. X.7680. BATTERY IGNITION DISTRIBUTOR ROTORS. In connection with the above my assistant's report WE.22. reads as follows :- "In connection with bench endurance tests carried out on ignition coils using standard distributors we have experienced several H.T. rotor failures due to the insulation between the blade and the cam breaking down. The conditions have been slightly more severe than might be expected to obtain on a standard chassis but it shows that there is very little margin. In view of the increased compression ratio of the 20/25 HP. the ignition conditions will become more severe for insulated components such as the H.T. rotor, and as the tendency is to still further increase the compression ratio (12-GIV is 5¾ : 1) the crown thickness of the rotor insulation should be still further increased to cope with the increased voltage required at the plugs." Perhaps you will see what can be done in the matter. EFC. {E. Fowler Clarke - Electrical Engineer} | ||