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).
Modifications and comparing the performance of a Smith Dynamo Type 2D against previous models and specifications.
| Identifier | WestWitteringFiles\F\May1921\ Scan62 | |
| Date | 31th May 1921 | |
| To R.{Sir Henry Royce} & E.{Mr Elliott - Chief Engineer} from EFC. c. CJ. & PN.{Mr Northey} c. Bn.{W.O. Bentley / Mr Barrington} & By.{R.W. Bailey - Chief Engineer} c. Da.{Bernard Day - Chassis Design} & EP.{G. Eric Platford - Chief Quality Engineer} c. EWT. for R.R.Inc. EFC3/T31.5.21. X.295 - SMITH DYNAMO TYPE 2D WITH R.R. MODIFICATIONS. Further to our EFC6/T13.4.21 and EFC1/T5.5.21, we attach photostat copy of some curves which show the ampere-hour output performance of the most recently received Smith dynamo, No.2111, in comparison with curves previously issued under cover of our EFC6/T13.4.21 showing the performance of dynamo No.2083, and still previous Smith dynamos, together with specified performance of dynamo for R.R. car. It will be remembered that, as reported in our EFC6/T13.4.21, the output of No.2083 did not meet our specification and upon this being pointed out to Messrs. Smith, they arranged that it should have a few more conductors in the armature to obtain the earlier cutting in. This modification they have carried out, resulting in the fact that this machine now very nearly complies with our specified performance, as will be seen by the curves. The output at the higher speeds, although considerably less than that of No.2083, nevertheless remains up somewhat higher than is asked for by our specified performance. Messrs. Smith have made to machine No.2111, as compared with No.2083, such minor modifications as were suggested by our Design Dept. and referred to in our EFC1/T5.5.21. Machine No.1111 appears quite silent as regards magnetic hum on the bench. It appears that in Contd. | ||