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).
Friction materials and a proposed redesign for damper wheels, including a cross-section diagram.
| Identifier | ExFiles\Box 138\1\ scan0036 | |
| Date | 24th May 1932 guessed | |
| (3) I have no confidence in going back to well lubricated ferodo unless it is free from gummy make up. (We could find what surface is best, and if dry is better then lubricated.) The material I have always favoured is 'vulcanised fribre', and I suggest it should be used thin so that the moisture does not make it take up all the clearance. The necessity of limiting the clearance perhaps does not exist in centrifugal loading. Anyway when we used this dry we did not seem able to make a bad slipper wheel - i.e. in the old days we could tighten up really tightly. Ignore for the moment the defect of this material swelling with moisture, and test if this surface dry and lubricated gives any advantage. Finally we ought to redesign our damper wheels, increasing the weight (inertia) all we possibly can. There can be no doubt that the greater the momentum of the wheel the greater the range of adjustment and the more effective it can be made. I hoped to send some better sketches, but out own type which we call 'low inertia' (disc only on crankshaft) seems the best. The wheel should be made of 2 stiff halves firmly bolted together just outside the disc, and one of the two friction surfaces carried by our flexible corrugated disc spring loaded to give the friction required. [Diagram Annotations] Top of diagram: Bolts. Left of diagram: Ferrule through window. Right of diagram, top: BOlts permanent. and rigid. Right of diagram, bottom: Grease retaining, two single row N.D. ball bearings if dry friction found superior As centrifugal loading with ordinary friction leads to complication we might find this/necessary with heavier wheel and dry friction. un I do not remember exactly if we prefer entirely free damper wheel, or if we can get any advantage by our internal spring in the end of the crankshaft. R.{Sir Henry Royce} | ||