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).
Summary of opinions regarding dynamo issues, comparing the 36 slot dynamo to the Bentley II type and discussing potential solutions.
| Identifier | ExFiles\Box 168a\3\ img084 | |
| Date | 30th March 1939 | |
| -3- Rm{William Robotham - Chief Engineer}/RC.{R. Childs}18/JH.30.3.39. time, coinciding with a warmed up condition of the commutator and brushes. We do not consider this serious as it has only happened on a few machines and has been cured by skimming. We are trying out a simple modification on C.J.A.? whereby the angle of the top of the brush has been increased from 5° to 30°. This to-date, appears to have cured the trouble. Summarising, we are of the opinion that - (1) The 36 slot dynamo is generally a better machine than the Bentley II type. (2) That to revert to the Bentley II type of dynamo, with the existing load conditions would tend to a future epidemic of failures on customers cars. (3) To revert to the lower outputs would mean a return to complaints of undercharging and the consequent running down of batteries, as experienced about a year ago. (4) Before standardising the new machine the commutator question must be thoroughly investigated. We must not reduce costs at the expense of quality The customer must be warned that any indications of erratic charging or vibration from the cutout calls for an examination of the dynamo brushes. However, we don't expect this to happen with normal conditions under 15,000 miles. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} | ||