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).
Technical note on centre-point steering and the effects of transversally raked pivots.
| Identifier | ExFiles\Box 178\1\ img108 | |
| Date | 13th July 1926 guessed | |
| - 9 - the pivot. This means in other words, when one front brake only is applied, the steering can remain unaffected. As pointed out under the sub-section on Braking, however, centre-point steering will not safeguard a car's steering unless the front axle is held rigidly in torsion. When both brakes are applied, there will be no strain on the cross steering tube. Obstructions hitting the wheel should have the minimum tendency to turn it. In practice, exact centre-point steering is bad for road shocks and promotes heavy steering when shunting, for the tyre has to be twisted on the ground instead of the slight rolling action which takes place when out of centre-point steering is used. The optimum practical results are obtained when Z the distance out of centre-point is between .500" and 1.00" (see sketch A.{Mr Adams}) (b) Transversally raked pivots. These are a means of obtaining centre-point steering. With wire wheels and front wheel brakes, some transverse rake is essential. If instead, the wheel camber to obtain this result is increased unduly, a considerable strain is necessarily thrown upon the wheels. A feature of raked pivots is that the car is lifted by a small amount whenever it is steered on a lock. If the pivot was turned through 90º in Sketch A.{Mr Adams}, the car would be lifted approximately distance Y. Though this makes the steering slightly heavier it is an advantage in a way, because it gives the steering an inherent self-centering tendency, this is because the weight of the car is always trying to force the pivots into their straight forward position. contd. | ||