Design improvements for the Wraith III front suspension, including the use of rubber mountings and Silentbloc bushes.
| Identifier | ExFiles\Box 9\5\ 05-page054 | |
| Date | 14th April 1937 | |
| SECRET. 646. E {Mr Elliott - Chief Engineer} /Ev. {Ivan Evernden - coachwork} 2/LN.14.4.37. To BY. {R.W. Bailey - Chief Engineer} Copy to DR. FHC. Rm. {William Robotham - Chief Engineer} HES. AHy/les. HY {Tom Haldenby - Plant Engineer} /NW. {N. Walker - Patents} ----------------- Re Wraith III Front Suspension. Reports from America and the results of our observations somewhat indicate the desirability of providing a certain amount of flexibility in the front wheel independent suspension. This is achieved on American cars in many cases by the use of rubber bearings to the triangle levers. We have already sent you the design for a rubber bearing at the lower end of the yoke piece with this object in view. We would also like to try a rubber mounting for the whole of the suspension at its attachment to the chassis frame, as at this point the rubber would have to accommodate no angular movement such as it does on the triangle lever bearings, and the result we feel should be somewhat comparable with that produced on the ordinary orthodox axle suspension where flexibility is provided transversely between the road wheel and the frame by the road springs. On N.Sch.5114 herewith we show the suspension forging attached to the frame by means of three Silentbloc bushes. The scheme can be fitted to an existing car. In order to produce the larger bosses on the forging to accommodate the Silentbloc bushes, we suggest that the Experimental Dept. could build up the bosses by welding. Although the bushes are overloaded according to the catalogue, their functioning in this position is not altogether orthodox, and we suggest that they could take the heavier load because they have no angular movement to deal with. We are sending a print of this scheme to Messrs. T.B.Andre for their comments. We suggest that the idea may be sufficiently novel to warrant a patent being acquired. The novelty consists of the attachment of the whole front suspension and frame extension to the main frame by means of rubber, and this rubber may take the form of a Silentbloc bush, a Cadillac bush, a Delco bush or even blocks of rubber sandwiched between the main forging and frame. We suggest to the Expl. Dept. that this scheme should be tried with a view to over- | ||
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).