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).
Axle control, suspension geometry, and its effect on steering and rebound.
| Identifier | ExFiles\Box 87\4\ scan0081 | |
| Date | 16th September 1935 guessed | |
| (sheet 2) downwards the full force of the springs is available to overcome the inertia alone. A rough calculation indicates that the torque causing precession is approximately three times as great downwards as upwards. So that the suggestion is that the adverse bump geometry is not important, because of the small forces encountered and improvement in the rebound geometry alone is sufficient to produce an impression of an improved steering. The quarrelling between the axle control movements and the spring movement is much more pronounced with the spring anchored at the front. With the standard arrangement there is slight quarrelling on full rebound but none on the bump. With the new arrangement there is pronounced quarrelling both on bump and rebound but especially on the rebound. The effect of the quarrelling is to cause the centre part of the axle forging and also the road springs themselves to some extent, to act as an anti-roll bar system. That this is so has been since confirmed experimentally. This should tend to reduce the effect of rebound by reducing its amount and its speed and so reduce the torque. It seems possible that both these phenomena act together to produce the improved result. The axle is of course stressed torsionally by twisting and it will be desirable to test for its endurance. If the gyroscopic effect of (1) and (2) is the primary cause of the improvement it will still be there if we move the axle control to the front as suggested by Hancock, but if (3) is the greater effect the improvement will be lost. The geometry of the brake cable is made worse by either arrangement with the spring anchored at the front, and it is difficult to see how it can be restored except by putting a reversing lever in front of the axle. It is proposed to investigate another well known jog ler, viz. Phantom, to see if it tends to confirm the above suggestions. Da.{Bernard Day - Chassis Design} | ||