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).
Outlining five key design requirements for hydraulic shock dampers.
| Identifier | ExFiles\Box 28\1\ Scan102 | |
| Date | 5th March 1927 | |
| +832 To OY. DA.{Bernard Day - Chassis Design} Hs.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} from R.{Sir Henry Royce} c. to BJ. Wor.{Arthur Wormald - General Works Manager} PN.{Mr Northey} CWB. R1/M5.3.27. HYDRAULIC SHOCK DAMPERS. X.235 X.832 I thank Mr. Olley for his memo. of Feb.18th. Many of the makers have not realised our points of view. They are :- (1) We cannot trust to viscosity for constant action, so we provide a spring loaded relief valve in each direction, (preferably loaded for different pressure.) (2) We must get rid of air, refill, and allow car to slowly settled into equilibrium. (3) We want force filling for quick action. (4) We cannot believe that we can retain the fluid unless the reservoir is below the gland. (5) We cannot waste time in either direction by a free centre part, or single acting, or any part of the stroke being idle, otherwise there is too great a force needed for the necessary damping in other parts of the stroke. We believe no other make than RR. fulfills these requirements and I cannot see how it is possible to meet them more efficiently, and with less cost and weight. We have spent much time, and thought, and testing on this matter, and have provided a similar scheme for steering, that we think for the present the subject has had its share of attention, and I am in favour of finishing by perfecting the reliability and economical production on these lines. R.{Sir Henry Royce} | ||