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).
Proposal for a variable hydraulic shock damper and steering system, controllable manually by the driver or automatically.
| Identifier | ExFiles\Box 55\4\ Scan023 | |
| Date | 16th February 1927 | |
| To Hs.{Lord Ernest Hives - Chair} DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} from R.{Sir Henry Royce} c. to BJ. Wor.{Arthur Wormald - General Works Manager} RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} PN.{Mr Northey} c. to Mr. Claremont. SHOCK DAMPERS, AXLE AND STEERING. X. 8430 X. 8420 X. 235 We have known for many years that shock dampers should be variable, either automatically or at the will of the drivers, from a minimum for slow speeds, increasing with high speed and rough roads. A few days ago it occurred to me that it was possible and perhaps practical to make them so by the following device - Since we are to have RR. hydraulic dampers on all 4 wheels, and perhaps on the steering, we might vary the load on the relief valves by arranging small hydraulic plungers above each valve, (probably using a spring for the minimum load). We could increase the relief pressure by creating an hydraulic pressure by a small pump driven by the car, say by the servo shaft. This hydraulic pressure could be variably controlled by a small lever near the driver's hand, or automatically by centrifugal governor driven by the car. (directly or indirectly according to the required law.) Naturally let us first consider if the hand control, by varying the spring pressure on the special relief valve on this proposed hydraulic system, would make an arrangement which was not too complicated for a large, powerful, luxury car: I think it may be found practical. It will be seen that 4 very small pipes would carry the pressure to the four or five points when there are two damper valves at each point. The pump only requires enough capacity to allow for the leakage (which would be the difficult item.) This might be returned after filling up the dampers, or the plungers might be diaphragms. Naturally there are other difficulties which I can see, but which may be surmounted without losing simplicity - (small air chambers over each valve to allow sudden opening.) It will be see that a similar scheme could be used to increase the pressure on the plates of a multi-plate friction damper, at will, or automtaically. There are many modifications that would suggest themselves, but the above is sufficient for a provisional patent if it is thought worth while, and also, Messrs. Day and Hardy might have a trial at an experimental design to see if such a scheme could be kept simple enough to be practical. R.{Sir Henry Royce} | ||