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).
Dynamo, cutout, and distribution box failures and recommended improvements.
| Identifier | ExFiles\Box 50\5\ Scan203 | |
| Date | 19th July 1923 | |
| - 2 - 3. Contd. be adopted generally, and possibly you may consider this being recommended to be done retrospectively. We have already had one or two further similar failures the chief of which have been the earth connection from the battery. I have been over this feature with Mr. Booth. 4. X4383 Dynamos. We have had four or five of these actually fail in service. The dynamos showed distinct signs of overheating, the solder having been thrown out from the conductor connections to the commutator. On these dynamos the condition of the commutator appears to be very badly blackened and burnt, also the brushes seem to be in very poor condition, the bedding having apparently changed from its original bedding as though the position of the brushes had changed. A dynamo of this type was today brought to the attention of Mr. Brock and EFC., and we have sent to EFC. a dynamo which although has not actually failed due to overheating has increased its output from its original setting, although no alteration or adjustment has been made to the dynamo since it came on test, and which we feel eventually will fail due to overheating. We are anxious to draw attention to the condition of the commutator brush gear, and also note that the nuts for the fixing brush gear at present are not tight, and the tightness of these we feel may be influenced by the alteration to the insulating material due to variation in temperature. The output automatically building itself up while running at present appear to be rather a common fault, and one which I shall be glad if EFC. can investigate, and give some specification whereby this can be improved. Personally I am of the opinion that the bedding and control of the third brush is not at present satisfactory. The output of the dynamo is considerably influenced by the load and bedding of this brush, and I feel that very definite instructions should be given that the adjustment of the output should not be finally settled until the correct load control and bedding of this brush has been obtained and will be maintained. (See late page 3.) 5. X4421 X4410 CUTOUTS AND DISTRIBUTION BOXES. Several of these have been returned having failed in service. The last one was returned to Mr. Brock on the 18th. inst. see memo EP{G. Eric Platford - Chief Quality Engineer}14/H19.7.23. In one or two of these cases, we are assured that it has been due to faulty batteries or battery connections, and in other cases due to faulty ignition | ||