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).
New armature scheme for a 6-volt dynamo intended for U.S.A. SS. models.
| Identifier | ExFiles\Box 60\1\ Scan105 | |
| Date | 19th April 1929 | |
| EY. from EFC. c. Ey/RD. EFCl/T19.4.29. 6-VOLT DYNAMO FOR U.S.A. SS.{S. Smith} We have schemed out an armature for this dynamo which utilises the same armature core, commutator and winding step as the present S.S. armature of the type approved for standard, the only difference being (1) That the section containing a lap coil is replaced by a standard section so as to make a perfectly symmetrical armature. (2) The connections to the commutator segments are differently made. The scheme worked out gives what may be called a duplex or doubly re-entrant wave winding and has four parallel paths through the armature so that with the same size of armature conductor it produces an armature directly suitable for 6 volts. As referred to above, its advantages are that it utilises all standard parts, and only differs in method of connecting up the conductor. A table and diagram of this winding is handed to EY/RD. and we are of the opinion that the moment the 6 volt scheme comes under serious consideration, an armature of this type should be instructed. (It will be very readily produced). For utilisation of this armature we shall need a standard S.S. carcase with field windings of 17 S.W.G. in place of 19 S.W.G. as at present, the number of turns in the 17 S.W.G. case being such as will conveniently make the coils a similar size, the exact number being unimportant. EFC. | ||