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 analysis of the possible causes and contributing factors of steering wobbles.
| Identifier | ExFiles\Box 28\4\ Scan181 | |
| Date | 19th February 1931 | |
| STEERING WOBBLES. We should like to make the following suggestions as to a possible cause of steering wobbles:- (1). The mass that is being oscillated is the whole sprung weight of the car, pivoted about the back axle, plus the front wheels. (2). The springyness about which it is oscillating is:- a). The tyres. b). The Front Road Springs. c). The Frame. d). The Top Steering Lever. e). The Side Steering Tube. f). The Springs in the Side Steering Tube. g). The Pendulum Lever. h). The Steering Worm Shaft - in the case of 7CA up to the thrust bearing - in the case of an ordinary wobbling car, up to the steering wheel. (3). The means by which this springyness is brought into play is the inclination of the front axle pivots, both in the front elevation and in the side elevation. If there were no inclination in the side elevation, the inclination in the front elevation causes the tyres, road spring etc., to be compressed on turning round, because the wheel is turning about a cone. The same effect is produced by the inclination of the pivots in the side elevation, except that in this case the tyre springs, etc., on one side are compressed, while on the other side the pressure is relieved momentarily, by turning the wheel. So that it is quite possible that when a front wheel is turned suddenly, at a particular speed, the mass of the car, carried on the above combined system of springyness, may develope a resonant period, which would be comparatively slow, but of considerable energy. Contd. | ||