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).
Improving car suspension by cross-connecting hydraulic dampers to counter shimmy and pitching.
| Identifier | ExFiles\Box 16\4\ Scan133 | |
| Date | 10th February 1930 | |
| To: Mr. Southern From: Mr. Olley Cc- Mr. Ainsworth Mr. Hives (Eng) Mr. Burton Mr. Elliott (Eng) SHOCK ABSORBERS (SHIMMY) Work on amphibian gears at Brewsters, operated hydraulically has brought out a feature of hydraulic dampers which might offer possibilities in car-suspension, namely that by cross-connecting a pair of hydraulic dampers, so that the upstroke side of the one communicates with the downstroke side of the other, a form of parallel motion can be produced. If the system were sealed this action would be perfect and no departure from parallel motion would be possible. Leakages in the system permit the development of damping action. For example suppose our two front shock absorbers were cross-connected in this way with the spring loads on the existing low and high pressure valves increased and restrictions in the cross-connecting lines, which communicate with the cylinder bores direct and not through the valves. One can imagine developing great damping action resisting criss-cross vibration of the axle without over-damping the front suspension. Also by cross-connecting front and rear shock absorbers, one could perhaps develop more damping against pitching than against bouncing. It is possible that Hs.{Lord Ernest Hives - Chair} might be interested in trying the effect of the first suggestion on PII. | ||