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 improvements and potential issues for hydraulic shock dampers.
| Identifier | ExFiles\Box 68\2\ scan0146 | |
| Date | 12th March 1926 | |
| To DA.{Bernard Day - Chassis Design} & BY.{R.W. Bailey - Chief Engineer} from R.{Sir Henry Royce} c. to Hs.{Lord Ernest Hives - Chair} E.{Mr Elliott - Chief Engineer} +8520 RL/M12.3.26. RE. HYDRAULIC SHOCK DAMPERS: X.235 N.SCH. 2153. X.8520 We must try to get this right without altering the leading dimensions. (1) I cannot understand why it should not work correctly until the inlet valve passages become uncovered. (2) The pistons may leak oil under the very heavy pressure but the suction should only be very light, and the leak of air inwards very little indeed, because one has the inlet valve to destroy the vacuum which only occurs at the samespeed as the leak. (3) Inlet ball valves might be larger and passages also, then piston would have less inducement to suck air. (4) Could piston have ring formed at bottom, or leather arranged to prevent ingress of air. Such leather would do nothing to prevent pressure escaping, and would not wear. It might be double for both ways. (5) RESTRICTED VENT. Your modification to my arrangement seems an improvement in convenience, but the screw above the ball might be screw-driver type countersunk, or counterbore the plug (having larger hexagon) for fibre washer. (6) The felt ring as shewn is difficult to get in effectively water tight. I think it would be better as originally modified to my later sketch, or screwed nut. Avoid all features on the lever: there is a lot of work difficult to make. (7) You will require a filler plug; you would not wish the top cover taken off for this purpose. It should be embodied with the breather - i.e. one item. (8) I should do all possible to make the oil retaining a success, therefore I shew a screwed gland. Thread the cover forming the cavity and screw on a nut. This will be put together before the shaft is pushed home. (9) The filter might possibly be a flat gauze at the bottom, thus - SEE ORIGINAL FOR SKETCH. The plug has waist perforated, gauze or cast bars, with a simple strip of gauze wrapped round and soldered. What you shew has too many features or pieces. I believe we can make this work with less parts and complication by my double valve in piston, and two inlets. (SEE ORIGINAL FOR SKETCHES). R.{Sir Henry Royce} | ||