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).
Technical memorandum discussing design improvements for shock dampers, focusing on glands and lever attachments.
| Identifier | ExFiles\Box 179b\1\ img287 | |
| Date | 27th January 1933 | |
| HDY{William Hardy} ) FROM R.{Sir Henry Royce} HS.{Lord Ernest Hives - Chair} ) DY.{F R Danby} ) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} to SG.{Arthur F. Sidgreaves - MD} WCR. ORIGINAL R1/M27.1.33. SHOCK DAMPERS. Anything we arrange will require care in getting together tightly, and the least treacherous way is to make the parts solid where-ever possible. Whenever we trust to good regular workmanship we come to grief generally, unless it refers to some important part like a connecting rod. GLAND. The most easy gland to get tight is one you can screw up at any time, such as is used on a pump rod or steam engine piston rod. RM.{William Robotham - Chief Engineer} brought me one fitted up with a large screw nut and locking plate, and I think this will give greater satisfaction than any of the so called near ways, either U. S. A.{Mr Adams}, or our own. INSIDE LEVER (FAILURE TO REMAIN TIGHT.) Considering that the key has sheared as well as the tight grip by bolt, and that the damper has broken the frame, it looks as though the damper is doing more than the legitimate load of 100 odd lbs. at the ball end, such as limiting the axle on bump or rebound by getting to the end of its stroke. If not then we must make the grip bear more loading before it moves, which ought to be capable of proof testing. The same applies to the outside lever. Personally I should give a better nut for the spanner that would tempt the fitter to tighten the bolt nearer to its limits, and I would delete the split pin. The outside lever could be on the full diameter of the shaft, so gaining about 20%. The inside one might be made a more or less permanent job, in which case I should either make it solid with the shaft, or parallel serrations which are put together for good, and always with press fit (no split.) If a split were used either with parallel Vee serrations, or as at present, it is still necessary to press in the shaft, and somewhat open the split, say 5 to 10 thous. We cannot expect either plain, serrated, or square, to press in by hand and grip firmly enough. (1) | ||