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).
Investigations into a pressure issue in hydraulic shock dampers, possibly caused by trapped air.
| Identifier | WestWitteringFiles\S\2April1928-June1928\ Scan142 | |
| Date | 22th June 1928 | |
| HS.{Lord Ernest Hives - Chair} FROM DA.{Bernard Day - Chassis Design} DA{Bernard Day - Chassis Design}1/M22.6.28. HYDRAULIC SHOCK DAMPERS. X235 With reference to HS{Lord Ernest Hives - Chair}/RM{William Robotham - Chief Engineer}2/LG18628., Mr. Royce suggests that the phenomenon of the pressure remaining on the high pressure side during the low pressure stroke may be due to a small amount of air trapped in the system. This could be investigated in various ways. One method would be to increase the size of the vent hole so that excess oil can be more readily ejected into the reservoir. Another way would be to prevent the replenishment of one or both of the cylinders by closing the replenishment valve. If the phenomenon is to do with kinetic energy it will presumably be tested by trying the indicator in different places. We presume you are quite sure that it is nothing to do with the indicator itself. With further reference to the tests it is suggested that one good way to verify the trapped air theory would be to close the vent while the damper is working. If there is air trapped the pressure should stay on the high pressure side all the time. We do not see very well where air can be trapped on the high pressure side, but it is possible that there may be some around the low pressure valve, or in the high pressure replenishment valve. DA.{Bernard Day - Chassis Design} | ||