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).
The 10,000-mile test of an experimental J-type N.B. dynamo, detailing issues with brush noisiness.
| Identifier | WestWitteringFiles\Q\December1926-January1927\ 54 | |
| Date | 10th December 1926 | |
| To R.{Sir Henry Royce} from EFC. c. BJ. Wor.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} Ey. Rg.{Mr Rowledge} c. EP.{G. Eric Platford - Chief Quality Engineer} EFC6/T10.12.26. ORIGINAL X.8671. EXPL. DYNAMO J OF THE N.B. TYPE, AFTER 10,000 MILE TEST ON 12-EX. This dynamo has recently been removed from chassis 12-EX, i.e some time after completion of the 10,000 mile test. It has been examined and tested in our laboratory and please find attached copy of my assistant's report PC.120 in this connection. The only complaint in connection with this machine on the 10,000 mile test was some amount of brush noisiness, and this is the sole reason why we have withheld circulation of a standardisation sheet for this type of machine. It has been previously reported that this type of machine produces far less self-heating for the same output than the present standard machine with the wider brushes. The commutation is equally good and brush wear is not materially increased. Brush wear is in any case comparatively small since the introduction of the 57 segment commutator. A report on the comparative brush wear of the wide and narrower brushes, as a result of tests made on the bench will follow. The noise, during our recent bench tests, did not appear to be more than is usual on other machines (wider brush machines). It was considered, however, that it might be improved by skimming the commutator; this was done and some amount of improvement was noticed. This machine has now been put back on the same chassis, replacing another of Contd. | ||