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).
Viability of using a moulded commutator, focusing on material stability under heat.
| Identifier | ExFiles\Box 50\5\ Scan097 | |
| Date | 15th July 1922 | |
| (EFC. {E. Fowler Clarke - Electrical Engineer} (Wor. {Arthur Wormald - General Works Manager} To (Ey. from R. {Sir Henry Royce} (E. {Mr Elliott - Chief Engineer} (Ds. (PN. {Mr Northey} X4333 R1/M15.7.22. X.4333 - RE COMMUTATOR. We shall not think of using a commutator built up by the moulded system until it has been clearly proved that there is no deterioration in strength and shrinkage in dimensions of the material used in the construction, when subjected to a temperature equal to the melting point of solder for several months. This is what we anticipate a dynamo may get in a long life of a car. To prove whether the ground is hopeless you want to find out whether the bakelite material deteriorates and shrinks, or whether it is only the filling which changes in condition. If it is the filling the situation is hopeful as a filling formed with asbestos fibre might be quite suitable for the purpose, and not change in time. If, however, it is the synthetic resin used to cement the filling together that shrinks or becomes brittle, then the situation is quite hopeless. In Mr. Clark's memo. of the 13th inst. he distinctly says that "Mouldensite" is the best material tested. He does not say where this comes from or whose name it is. We presume it is not "Fleming's material and possibly not the Bakelite Co's material, but is obtained through some other channel. I would like him to tell us where this comes from. X. 4069. Regarding the commutators for starter motors these possibly we could continue to make by the moulding Contd. | ||