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).
From 'R' discussing design modifications to strengthen a gearbox fabric coupling.
| Identifier | ExFiles\Box 180\M3\M3.5\ img019 | |
| Date | 1st April 1925 | |
| ORIGINAL FROM R.{Sir Henry Royce} H3/AGS. 4. 25. C. to [REDACTED] MR. H3. re. GEARBOX FABRIC COUPLING. X8305 X.8310 EWA I regret we did not in the first place find from the makers that the thin disc was not strong enough for the simple torque. It is a relief to know that we ought to get success if we make it 50% stronger, and we can make it 100%. The great point is we are not asking it to bend through any considerable angle so that it should be lasting if it will stand the torque of the clutch: this the makers promise. I am expecting that you can get it down fairly easily if you use a removable stud or set screw. [Diagram 1 Caption] Instead of [Diagram 2 Caption 1] Ordinary nut. [Diagram 2 Caption 2] Smaller hexagon on square for withdrawing stud. I notice that you cannot make it thicker than ½" unless you carry out the starter drive. This should be done if possible because we would like .9 thick, and thicker plates, and perhaps fairly thick washers. The drive would have to go out .150 for thicker fabric, and an extra .050 for added thickness to one plate; the other extra thickness would come off face of gearbox spider. I presume a nut cannot be behind the gearbox spider, but there seems room on the drawing. Let all the parts be made as substantial and out of the solid if possible. There would be no economy in saving cost at the expense of strength as we have no strength to spare. This coupling was not very seriously worked at originally by me as it was suggested as a possible alternative. We ought to have found that it was too weak however. R.{Sir Henry Royce} | ||