Steering issues, analysing the effects of friction, wheel dish, and pivot pin arrangements on wheel oscillation.
| Identifier | ExFiles\Box 49\4\ Scan069 | |
| Date | 23th April 1920 | |
| Contd. -2- Hsl/LG23.4.20. that the steering under this condition was quite good. There was no tendency for the car to run to one side without touching the wheel and the car kept a straight line. With the wheels fitted in this way the friction appeared about half what it was when both wheels were dished outwards. It still damped out the oscillations of the steering wheel and had the advantage of being lighter than when both wheels were dished outwards. The increased friction we get when we have the wheels so that they are 4 1/2" from the centre point must, we think, come from the extra load put on the pivot pin bearings. If this is so, then it gives a reason why the oscillation of the steering wheel of the present cars is worse than it used to be. It means that as we bring the wheels over the pivot pin, if we wish to retain the same amount of friction, we ought to add friction by some other means. It is only after the car has run 4000 to 5000 miles and the whole of the steering gets free that the oscillation of the steering wheel becomes objectionable. Seeing that the friction in the pivot pins does tend to damp out any steering wheel oscillations, we have been trying again your suggestion for plain thrust washers on the pivots instead of the ball. We find that if we have both pivot pins with plain washers, the friction is rather more than we like. So far, we find we get better results if we only have plain thrust washers on one of the pivots. We consider that on a present standard car the best arrangement for the steering is as follows:- 1. Pivot lean .25" backwards. Contd. | ||
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).