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).
Telephone message discussing design improvements for a starter armature and associated components.
| Identifier | ExFiles\Box 64\4\ scan0154 | |
| Date | 27th December 1928 | |
| X.7655B Telephone message from W.W. 27.12.28. Referring to your EFC/T7.12.28, my idea of the taper armature is probably wrong because (1) Feeble torque (2) Feeble initial pull Therefore let us abandon the taper and I suggest increasing the gauge of the teazer winding so as to make the operation vigorous. The hold-out spring should have the lowest rating possible, i.e., even pull end to end of its stroke, and sufficient to hold the weight of the armature out against gravity of 1 in 4 incline, i.e. it will be 1/4 the weight of the armature. Get this by comparison with Bosch. The kick back spring should be gentle at first engagement. It is rather high rating. Most of these are old suggestions. We must not mind the knock on final engagement or coming out. We must cure this by other means than making the action feeble to get this silence, which I think has been a mistaken idea at Derby. Naturally bearing and brush friction should be kept low and we might try the brushes with more carbon and less copper rather than weak brush holder springs that you may be tempted to try. E.{Mr Elliott - Chief Engineer} will arrange an effective oil dash pot to make the action silent at the end, and it is necessary to get the gears right for the starter to be silent when rolling the engine, both (2) and (3) of your memos depend on good gears. Starter on EAC.7 is working well and is measurable with our old starter. This is over 1 year old. R.{Sir Henry Royce} | ||