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).
The performance and proposed modifications for dampers, valves, and related components.
| Identifier | WestWitteringFiles\V\December1930-February1931\ Scan004 | |
| Date | 2nd December 1930 | |
| -4- He/31.1/AL.2.12.30.Contd. in such a case would appear to be to allow sufficient capacity above the oil level in the atmospheric chamber to take care of oil so expelled. This chamber would also permit of expansion of the oil and air in the damper without the necessity of providing an air vent. The ball valve should free itself after one or two strokes. The foreign matter that gets under the replenishing valve and in the air vent appears to be aluminium and comes from the inside of the damper. One disadvantage of the aluminium cylinder is that it flakes rather easily when it picks up. PIN JOINTS. We have already pointed out the effect of a minute amount of wear on these parts and for this reason have asked for increased bearing area. We have proved that the existing joints wear very rapidly unless submerged in the oil and that splash lubrication cannot be relied upon unless controlled and directed definitely upon the surfaces. The ideal is undoubtedly for these pins to be lubricated as long as there is sufficient oil in the dampers for it to work at all. AIR VENT. If the air vent is in the shape of a fixed orifice, experience has shown that with an aluminium cylinder it requires some sort of protection against bits of metal which may choke it. REPLENISHING VALVES. Collapse of the pin retaining the ball on the front damper has shown the violent hammering that takes place. Where two replenishing valves have been used this trouble has not been so noticeable. SHORT LEVERS TO FRONT DAMPERS. From the car control point of view we believe that removing spring in the levers and shafts of the front dampers as projected will have more effect than on the rear as smaller spring movements have to be dealt with. DRILLED VALVES. Our diagrams show that up to one .055 hole in H.P. valves of the Phantom ll damper we do not lose efficiency for 1" strokes. Actually the maximum pressures reached are less but the area of the diagram is greater. We will let you have a complete report on this feature later. Also diagrams taken under various other conditions. ATTACHMENT OF DAMPERS TO FRAME. In view of our present feeling that for certain conditions spring is undesirable in the shock absorber connections, it is worth noting that the 25 HP. brackets | ||