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).
Analysis of shock damper performance, limitations, and design considerations regarding pressure, velocity, and ride comfort.
| Identifier | WestWitteringFiles\S\March1928-May1928\ Scan068 | |
| Date | 30th March 1928 guessed | |
| contd :- -3- as the desirable pressure rise at a piston velocity of 14 ins/sec. because this is equivalent to a rise of 400 lbs/sq.in. at a piston velocity of 10 ins/sec, which is about the maximum we can use without spoiling our low speed riding. This is actually about the figure on the rear shock absorbers of the car at Le CanadelHenry Royce's French residence. It occurred to us that the pressure velocity factor might be made the adjustable portion of the damper by moving the orifices. We have been considering how we can further develop the shock dampers with a view to catering for the present tendency to use flexible springs, and small buffer clearance to keep the overall height of the car down. So far we have established (1) That we cannot have any central free motion without any damping or we get axle bounce and poor road holding and braking. (2) That we cannot have widely different up and down loads or we get an objectionable crick in the neck when the axle has gone away from the frame after a bump. This is if the high pressure loading is too high. It makes us feel that we do not want a great deal of damping when the spring is approach-ing maximum rebound or in other words, that the damping may with advantage tend to be proportional to the energy stored in the spring. (3) That at present we are limited as to the pressure velocity increase we can employ due to the fact that the axle has to move rapidly over small amplitudes to give good Boulevard riding, but that a compromise gives us the best all round results (14-EX rear). contd :- | ||