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 servo output distribution, the effects of friction at various bearings, and the impact of mechanism geometry in forward and reverse gears.
| Identifier | ExFiles\Box 105\4\ scan0135 | |
| Date | 19th April 1934 guessed | |
| -2- It can be seen that there is a considerable difference between the front and back outputs but that it is in the direction opposite to that which was anticipated. The low rating spring balance was then put at the back and the high rating balance at the front. The results with this arrangement are shown by curve 2. The variation from curve 1 is within the accuracy of the spring balances so that it can be said that the friction at the bearing (A) has no appreciable effect on the distribution of the servo output. In both curve 1 and 2 the output to the front is considerably greater than to the back with the servo running forwards. Friction at the centre bearing (E) of the balancer lever could cause this. To eliminate this friction a needle type roller bearing was fitted at (E) but the results were identical to those with the plain bearing. This shows that the friction at this bearing has a negligible effect. The greater output to the front must be due to the fact that the link (D) is not parallel with the swinging arm (B) and the amount of variation is in agreement with the geometry of the mechanism. In reverse gear the variation is the opposite way round and considerably greater. This is shown by curve 3. This again is in agreement with the geometry of the mechanism as the link F.{Mr Friese} is inclined at a greater angle to the swinging arm (B) and in the opposite direction. The difference between the distributions of the servo output in forward and reverse gear is an advantage as it is the same way round as the difference in the distribution of the weight of the car when braking in forward and reverse directions. Hs{Lord Ernest Hives - Chair}/F.J. Hardy. | ||