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 use of a Wimperis Accelerometer on railways.
| Identifier | ExFiles\Box 113\2\ scan0018 | |
| Date | 14th November 1922 guessed | |
| WIMPERIS ACCELEROMETER 3 ON RAILWAYS It happens that at the present time two of the matters most prominently in the minds of Railwaymen, are— (1) The handling of Suburban Traffic. (2) The safety of high speed trains when rounding curves. Universal experience has shown that the handling of dense suburban traffic requires a high acceleration on starting, and a rapid braking when stopping. Without these it is not possible to maintain the high schedule speed which will attract traffic to the line. Both, however, cause considerable stresses on the rolling stock, and it is important so to regulate the acceleration and braking arrangements that these additional stresses shall be as small as possible and that any irregularity or raggedness in operation shall be removed. Not only is “raggedness” of this kind bad for the stock, but it is unpleasant for the passengers and militates against the popularity of the service. These troubles, when found to exist, are usually removed, either by modifications in the equipment or by improved skill on the part of the drivers. Before these remedies can be applied, however, it is necessary to investigate the nature of the defects they are intended to remedy. For this purpose an instrument called an “accelerometer” is used. In its most useful form it makes a permanent record on a moving roll of paper of the motions of the train. Those to whom such Recording Accelerometers are useful are— (1) Railway Officers who have to consider the relative merits of the various systems of electrification accessible to them, and (2) Railway Officers in charge of electrified sections of their own Railway System. It is found that passengers are attracted when the schedule speed is high and when the rate of getting up speed is smooth and not ragged. Different systems differ much in this respect. At present the smoothest operation is attained where single phase equipment is used, but there is room for improvement in all. The object to aim at is not to allow the acceleration to begin or to end too suddenly; a gradual smoothing of the acceleration-time curve greatly increases the comfort of travelling by the avoidance of sudden shock, and lengthens the life of the stock. ELLIOTT BROTHERS, (LONDON) LIMITED. Established 1800. CENTRAL BUILDINGS, WESTMINSTER, LONDON, S.W., AND CENTURY WORKS, LEWISHAM, LONDON, S.E. | ||