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).
Potential improvements to car dynamos based on findings from aero engine experiments.
| Identifier | ExFiles\Box 168a\3\ img134 | |
| Date | 18th January 1934 | |
| 6099 E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wst. c. to Hy.{Tom Haldenby - Plant Engineer} Hs{Lord Ernest Hives - Chair}/Wst.11/MA.18.1.34. CAR DYNAMOS. During a conversation we had recently with the Aero engine dynamo expert from the Royal Aircraft Establishment we elicited the fact that after carrying out a number of experiments at Farnborough on aero dynamos they had proved that a much improved efficiency with consequent reduced losses could be obtained with :- (a) Only having one coil per slot instead of a multiple. We have two coils per slot. (b) Adhering to the straight slot instead of the much favoured semienclosed slot. We have always had straight slots. (c) Deleting all dummy coils. These results are very interesting because at the moment we are exploring every avenue in the direction of reduced armature losses. We are anxious therefore to try out a 40/50 type of dynamo with the following modifications :- (a) 49 slots i.e. without a dummy or lap coil. We are of the opinion that the large increased number of slots will reduce the noise which would normally arise with an odd number of slots. (b) One coil per slot consisting of 4 turns per coil of 16 S.W.G. D.C.C. Superfine wire. We should be glad if you will agree to an armature being schemed out and instructed for experimental test. Hs{Lord Ernest Hives - Chair}/Wst. | ||