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).
Analysis of issues with Lucas cut-outs in R.R. cars and a description of the testing methodology used to investigate them.
| Identifier | ExFiles\Box 36\4\ scan 035 | |
| Date | 14th May 1920 | |
| Contd. -4- EFE1/T14.5.20. and spring tension — gap curves of the moving mechanism, complicated by the frictional effect which leads to indefin- iteness. Although these Lucas cut-outs have no doubt in many instances given satisfactory results in practice, we are now of the opinion that they have decided faults and are not really excellent enough as a fitting for the R.R. car. We think that a lot of the complaints of late cutting in point, generally blamed on the dynamo, may be largely due to the cut-out. For the table given on sheet C, all cut-outs were tested on the same dynamo. We have, however, made tests with the six dynamos and six cut-outs paired together at random, which tests are exhibited in the tables below in a manner exactly similar to results of tests already given in our Ck{Mr Clark}2/T16.3.20 for combinations of Lucas and Smith dynamos with their respective cut-outs. For convenience we repeat the four conditions :- Having made the necessary connections of dynamo, cut-out, battery and instruments - (1) The dynamo speed was gradually increased until the cut-out was just operated and at the instant of operation the dynamo volts and speed were noted and recorded. Contd. | ||