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).
Testing and production costs of a narrower brush type dynamo.
| Identifier | WestWitteringFiles\P\2July1926-September1926\ Scan054 | |
| Date | 13th August 1926 | |
| ORIGINAL To R.{Sir Henry Royce} from EFC. c. to BJ. E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} HY.{Tom Haldenby - Plant Engineer} c. to Wor.{Arthur Wormald - General Works Manager} X.8671 - EAC. DYNAMO OF THE NARROWER BRUSH TYPE. Referring to your R2/M25.6.26, we have now two of these dynamos running under working conditions on chassis, one of which is on 10,000 mile car 12-KX in France. We have temperature indicating fusible metal sentinels to indicate the temperature reached on these, as also on other (standard) dynamos on chassis. We agree that the superiority of the thinner armature plates, as reported in EFC3/T21.6.26, is not particularly marked. As regards the cost on production of the armature tested with thin iron plates and mica separating plates, as compared with the present standard armature with thicker armature plates and mica separating plates, this we are given to understand would be 12/1d. per armature for plates and micas as against 6/8d. per armature in the standard case. In a recent visit of a representative of Sankeys, samples were shewn of punched armature plates to demonstrate how accurately these can be produced. We are having an armature made up with such punched plates and only varnish separation in order to see if the slight gain is maintained. We have tested the most expensive thin plate armature as compared with the standard - now we propose to test the least expensive thin plate armature as compared with standard. Should this shew the same superiority as the one already tested, probably the change would be worth while, otherwise | ||