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).
Design of rear cushions to improve passenger comfort and ride quality.
| Identifier | ExFiles\Box 132\3\ scan0223 | |
| Date | 5th September 1934 | |
| To. Mr. [illegible] FROM Mr. [illegible] Copy to E.W.E. (for O.F.O.C.) Mr. ..., Mr. Hives. J.E.R. McDu...dale x4524 re:- CUSHIONS. -------------- You will remember that we wrote to you several weeks ago about the rear cushions of our car and particularly that of your own car. We recollect that Bm was going to investigate the riding of the back seats of our Trials cars and we would be interested to hear the results of his investigations. We believe that we could do a lot to improve the comfort of our cars by treating the design of the rear cushion. In general it is customary to think of the rear suspension as the suspension of the chassis, whereas one ought to think of the suspension of the passenger. This consists of three parts, the tyres, the springs and the cushions and is affected by the weight distribution and the seating position relative to the axle. The tyres have been designed to have as low a rating as possible and sufficient inherent damping. We have done all we know to improve the springing by the use of low rating springs and hydraulic dampers of the governed type. Weight distribution and seating positions are dictated to us in a large measure by the body design. The one remaining item which has not changed progressively with the suspension is the cushion. Just like the tyres and the springs it needs to have a low rating with adequate damping. Because with the present spring case design one achieves very little damping, and in consequence the springs have to be stiffer than is desirable to prevent "bottoming", the passenger is bounced about excessively. In several cases we have found that an improved ride is obtained by removing the cushion and sitting on a folded rug on the seat-board. It is very misleading to judge the comfort of seats when the car is stationary, because an undamped cushion of low rating springs is a luxurious armchair, but a terrible cushion for a motor-car, whilst a damped cushion when first sat on to feels a little hard. The best cushion we know of is the "Solid Latex". The cushions we now use have a 2.000 in. layer of Latex | ||