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).
Design considerations for a horizontal damper, including cylinder types, lever attachments, and bushes.
Identifier | WestWitteringFiles\V\March1931-September1931\ Scan139 | |
Date | 22th April 1931 | |
ORIGINAL HS{Lord Ernest Hives - Chair}/RM.{William Robotham - Chief Engineer} FROM DA{Bernard Day - Chassis Design}/HDY.{William Hardy} C to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} BY.{R.W. Bailey - Chief Engineer} HORIZONTAL DAMPER. DA{Bernard Day - Chassis Design}/HDY{William Hardy}1/M22.4.31. Y 2355 We thank you for your HS{Lord Ernest Hives - Chair}/RM{William Robotham - Chief Engineer}5/K117431. We agree that the solid ended cyl. is likely to be cheaper and is of course oiltight. There are however one or two disadvantages given by the two detachable covers, viz: (1) The replenishment valves are both accessible without the removal of the inner lever. To what extent the valves need to be accessible in our new design we cannot say and until we have had first hand experience we doubt whether we shall know. Assuming that some attention will be necessary we feel that it is decidedly undesirable that the inner lever (clamped on a square or parallel serrations) should have to be removed and replaced, particularly as this is liable to be undertaken by outside mechanics. We do not think that the idea of having one valve in the piston and one in the cyl. is a good solution as this does not make for the same pieces and operations. (2) The damper body has to be R.{Sir Henry Royce} and L.H. when one end is solid. (3) The Works prefer a clear bore for machining. FIXED LEVER INSIDE OR OUTSIDE. Taper serrations are definitely superior to a clamped square or parallel serrations, but are not easily used inside the damper. We doubt that taper serrations need be much more costly than parallel serrations and we know of several instances of their use on American productions. A square appears to be the cheaper job and in some ways superior to clamped parallel serrations as we think that the distribution of load in the latter is a very uncertain matter and largely dependent upon the initial fit. BUSHES. We agree that the dampers should be tried without a bush for the tail end of the shaft but we can much reduce the expense of the facing operation for locating the lever sideways by having one bush. With regard to Delco dampers these may prove to be 100% as you suggest but we certainly have not yet had sufficient experience to know that they are. We know from experience with our own productions that months of usage on many cars are required before we have full knowledge of their performance and failings. DA{Bernard Day - Chassis Design}/HDY.{William Hardy} | ||