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).
Rectifying faults related to brush alignment, bedding, and output in a machine, possibly a dynamo.
| Identifier | ExFiles\Box 50\5\ Scan207 | |
| Date | 25th July 1923 | |
| Contd. -2- EFC3/T25.7.23. These faults of alignment and bedding were rectified by us and then it was found that the maximum output on the production test had returned to 10 amperes, at which presumably it had been originally tested. Though not exactly relevant, it might be mentioned in passing that in the negative brush, there was embedded a small piece apparently of metal which was causing the commutator to be scratched. We have once previously had a case of this, so thought it desirable to mention the possibility of the fault, probably occurring in the manufacture of the brush. Machine No.501 was handed to us by Mr. Brock as an example of the second case referred to above. In this case it appeared to be purely a question of brush bedding. It appeared that the negative brush and to some extent the control brush was not sufficiently perfectly bedded, as we were able to by carefully bedding these brushes to bring the machine into a condition such that the peak output could be got down to the scheduled amount (now 11 amperes) with the control brush position within the range provided, though admittedly the position found was rather near to the end of the range. We are prepared to allow an extra slot length of .100" on the advance side and suggest that Ry. puts through an alteration to this effect. This should meet every extreme case, provided the brushes are correctly bedded. It is not our experience that one of these dynamos with brush gear properly adjusted | ||