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).
Design modifications for a dynamo, including changes to the pole, brush sizes, and carcase.
| Identifier | ExFiles\Box 39\2\ Scan072 | |
| Date | 1st June 1921 | |
| Contd. -2- EFC5/T1.6.21. He considered the cross sectional area of the pole for the previously designed machine too large and that we should reduce this so as to get on more turns for excitation. The polar arc should be kept closely to 70% of the polar pitch. All dynamos considered by us for the present will be of the simple single field winding third brush control, exemplified by the Rotax AT.12 machine. X.3945 x 33/48 Mr. Royce fixed up two standard sizes of brushes which we should use, the larger being 1" by 3/8" and the smaller 3/8" by 5/16" in the cross section. He considered that this Goshawk I dynamo could be provided with brushes of the smaller standard. The carcase of the Goshawk dynamo he stated should be thinned down to .275". It was left that Mr. Elliott would send through sketches and drawings showing the new dimensions, after which we would send the necessary complete electrical calculations and the expected performance of the machine. EFC. | ||