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).
Investigation into the difficulty of improving the dynamo armature for a Phantom III.
| Identifier | ExFiles\Box 168a\3\ img271 | |
| Date | 21th January 1936 | |
| 86142 E.{Mr Elliott - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Wst. BY/RDS/W.21.1.36. "PHANTOM III". DYNAMO ARMATURE. Referring to the discussion and inspection of the ventilated dynamo from Chassis 31.EX and the new proposed armature recorded in E2/HP.16.1.36, we have set this proposal out, i.e. 36 slots. 18 S.W.G. wire. 12 conductors per slot. and find that by using a 3.100" dia. armature we obtain .045" width of iron in the neck of the armature teeth, this amount being insufficient electrically and mechanically. Furthermore, to produce a commutator having 72 bars, each bar to be sufficiently wide to take the armature conductors of .048" dia., would necessitate a commutator 3.300" dia., which is larger than the actual armature. This investigation proves the difficulty of improving an armature of so small a diameter. BYARD. | ||