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).
Formulas for calculating coil spring and wheel ratings, and discussing the effect of rubber bushes.
| Identifier | ExFiles\Box 154a\2\ scan0280 | |
| Date | 30th March 1939 | |
| - 3 - Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions}10/G.30.3.39. From the various ratios established it follows that :- For B.V. rating at wheel = Coil spring rating x (.85 x 1.13 / leverage squared.) + 23 Rating at wheel = Coil Spring rating x (.85 x 1.13 / 1.7242) + 23. = (Coil spring rating x.323) + 23 lbs/in. or Rating of required coil spring = (Rating at wheel - 23) / .323 lbs/in For B.50, we have :- Rating at wheel = (Coil spring rating x .3125) + 23 lbs/in. or Rating of required coil spring = (Rating at wheel - 23) / .3125 lbs/in It seems probable that the rating of the rubber bushes will be reduced as deterioration occurs, and an even more accurate approximation might be obtained by taking a mean rate for the rubber bushes. In order to obtain this a rating figure for a set of rubber bushes about to be scrapped is required. Da{Bernard Day - Chassis Design}/DB{Donald Bastow - Suspensions} | ||