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).
Theoretical considerations and suggestions for the manufacture of road springs.
| Identifier | WestWitteringFiles\V\March1931-September1931\ Scan197 | |
| Date | 19th May 1931 | |
| HS.{Lord Ernest Hives - Chair} ) FROM DA.{Bernard Day - Chassis Design} PY. ) [crossed out] ORIGINAL RECEIVED 20 MAY 1931 ROAD SPRINGS. DA{Bernard Day - Chassis Design}1/M19.5.31. x7410 x5410. With reference to HS{Lord Ernest Hives - Chair}/RM{William Robotham - Chief Engineer}3/KT13531., we do not wish to be dogmatic about the manufacture of springs as we know that our theoretical considerations cannot be strictly applied. We are also aware that in the following we are going back on what we have previously written to some extent. In looking over the information regarding the stresses in the plates we see that the free camber of the main leaf on the front spring is given as 3", the initial deflection of the whole spring being 4". It appears to us that insufficient advantage is taken of the fact that the main plate could be made to have very little stress in the loaded position, that is to say, instead of a free camber of 3" we suggest there might be one of 1" or 1.5" in which case the plate could be increased in thickness in the case of the 1.5" initial camber to apparently about .3", which should be adequate for the purposes of braking. We are aware that this to some extent spoils the spring, that is to say, the lower plates have to be more in number, thinner, and therefore heavier, but we think in view of the difficulties you are experiencing it would be worth experimenting in this direction. We expect that with a stress of round about 100,000 there is not much difficulty anticipated from the rear springs. DA.{Bernard Day - Chassis Design} | ||